En septembre 2019
Re,
Piqué par la remarque d'Adriane sur l'exo 12, j'ai un peu réfléchi à la question et on voit que la conjecture faite est fausse. La raison de base en est que si un nombre a la ppté demandée, on peut en fabriquer un nouveau en prenant par exemple (ce n'est pas le seul moyen)le nombre obtenu en dédoublant ,détriplant, etc... l'écriture du nombre n: p.exn=2178 satisfait la ppté alors n#n=21782178 aussi et n#n#n=217821782178 itou (en multipliant le nombre n par 4 on obtient son renversé et donc il a le même nombre de chiffres: on a donc 4(n#n)=(4n)#(4n) (pas de retenue dans les ops.) et en renversant, on a 
renverse(n#m)=renverse(m)#renverse(n))

Ceci dit, il est vrai que les deux chiffres les plus à gauche sont 21 et les plus à droite sont 78

Bon WE
JC

Voila une liste de nombres OK (normalement tous les nbres avec la ppté demandée comportant moins de 23 chiffres):Nb chiffres: 2
Liste vide
Nb chiffres: 4
n= 2178  4n= 8712  n renv.= 8712 ppté: True
Nb chiffres: 5
n= 21978  4n= 87912  n renv.= 87912 ppté: True
Nb chiffres: 6
n= 219978  4n= 879912  n renv.= 879912 ppté: True
Nb chiffres: 7
n= 2199978  4n= 8799912  n renv.= 8799912 ppté: True
Nb chiffres: 8
n= 21782178  4n= 87128712  n renv.= 87128712 ppté: True
n= 21999978  4n= 87999912  n renv.= 87999912 ppté: True
Nb chiffres: 9
n= 217802178  4n= 871208712  n renv.= 871208712 ppté: True
n= 219999978  4n= 879999912  n renv.= 879999912 ppté: True
Nb chiffres: 10
n= 2178002178  4n= 8712008712  n renv.= 8712008712 ppté: True
n= 2197821978  4n= 8791287912  n renv.= 8791287912 ppté: True
n= 2199999978  4n= 8799999912  n renv.= 8799999912 ppté: True
Nb chiffres: 11
n= 21780002178  4n= 87120008712  n renv.= 87120008712 ppté: True
n= 21978021978  4n= 87912087912  n renv.= 87912087912 ppté: True
n= 21999999978  4n= 87999999912  n renv.= 87999999912 ppté: True
Nb chiffres: 12
n= 217800002178  4n= 871200008712  n renv.= 871200008712 ppté: True
n= 217821782178  4n= 871287128712  n renv.= 871287128712 ppté: True
n= 219780021978  4n= 879120087912  n renv.= 879120087912 ppté: True
n= 219978219978  4n= 879912879912  n renv.= 879912879912 ppté: True
n= 219999999978  4n= 879999999912  n renv.= 879999999912 ppté: True
Nb chiffres: 13
n= 2178000002178  4n= 8712000008712  n renv.= 8712000008712 ppté: True
n= 2178219782178  4n= 8712879128712  n renv.= 8712879128712 ppté: True
n= 2197800021978  4n= 8791200087912  n renv.= 8791200087912 ppté: True
n= 2199780219978  4n= 8799120879912  n renv.= 8799120879912 ppté: True
n= 2199999999978  4n= 8799999999912  n renv.= 8799999999912 ppté: True
Nb chiffres: 14
n= 21780000002178  4n= 87120000008712  n renv.= 87120000008712 ppté: True
n= 21780217802178  4n= 87120871208712  n renv.= 87120871208712 ppté: True
n= 21782199782178  4n= 87128799128712  n renv.= 87128799128712 ppté: True
n= 21978000021978  4n= 87912000087912  n renv.= 87912000087912 ppté: True
n= 21978217821978  4n= 87912871287912  n renv.= 87912871287912 ppté: True
n= 21997800219978  4n= 87991200879912  n renv.= 87991200879912 ppté: True
n= 21999782199978  4n= 87999128799912  n renv.= 87999128799912 ppté: True
n= 21999999999978  4n= 87999999999912  n renv.= 87999999999912 ppté: True
Nb chiffres: 15
n= 217800000002178  4n= 871200000008712  n renv.= 871200000008712 ppté: True
n= 217802197802178  4n= 871208791208712  n renv.= 871208791208712 ppté: True
n= 217821999782178  4n= 871287999128712  n renv.= 871287999128712 ppté: True
n= 219780000021978  4n= 879120000087912  n renv.= 879120000087912 ppté: True
n= 219782197821978  4n= 879128791287912  n renv.= 879128791287912 ppté: True
n= 219978000219978  4n= 879912000879912  n renv.= 879912000879912 ppté: True
n= 219997802199978  4n= 879991208799912  n renv.= 879991208799912 ppté: True
n= 219999999999978  4n= 879999999999912  n renv.= 879999999999912 ppté: True
Nb chiffres: 16
n= 2178000000002178  4n= 8712000000008712  n renv.= 8712000000008712 ppté: True
n= 2178002178002178  4n= 8712008712008712  n renv.= 8712008712008712 ppté: True
n= 2178021997802178  4n= 8712087991208712  n renv.= 8712087991208712 ppté: True
n= 2178217821782178  4n= 8712871287128712  n renv.= 8712871287128712 ppté: True
n= 2178219999782178  4n= 8712879999128712  n renv.= 8712879999128712 ppté: True
n= 2197800000021978  4n= 8791200000087912  n renv.= 8791200000087912 ppté: True
n= 2197802178021978  4n= 8791208712087912  n renv.= 8791208712087912 ppté: True
n= 2197821997821978  4n= 8791287991287912  n renv.= 8791287991287912 ppté: True
n= 2199780000219978  4n= 8799120000879912  n renv.= 8799120000879912 ppté: True
n= 2199782178219978  4n= 8799128712879912  n renv.= 8799128712879912 ppté: True
n= 2199978002199978  4n= 8799912008799912  n renv.= 8799912008799912 ppté: True
n= 2199997821999978  4n= 8799991287999912  n renv.= 8799991287999912 ppté: True
n= 2199999999999978  4n= 8799999999999912  n renv.= 8799999999999912 ppté: True
Nb chiffres: 17
n= 21780000000002178  4n= 87120000000008712  n renv.= 87120000000008712 ppté: True
n= 21780021978002178  4n= 87120087912008712  n renv.= 87120087912008712 ppté: True
n= 21780219997802178  4n= 87120879991208712  n renv.= 87120879991208712 ppté: True
n= 21782178021782178  4n= 87128712087128712  n renv.= 87128712087128712 ppté: True
n= 21782199999782178  4n= 87128799999128712  n renv.= 87128799999128712 ppté: True
n= 21978000000021978  4n= 87912000000087912  n renv.= 87912000000087912 ppté: True
n= 21978021978021978  4n= 87912087912087912  n renv.= 87912087912087912 ppté: True
n= 21978219997821978  4n= 87912879991287912  n renv.= 87912879991287912 ppté: True
n= 21997800000219978  4n= 87991200000879912  n renv.= 87991200000879912 ppté: True
n= 21997821978219978  4n= 87991287912879912  n renv.= 87991287912879912 ppté: True
n= 21999780002199978  4n= 87999120008799912  n renv.= 87999120008799912 ppté: True
n= 21999978021999978  4n= 87999912087999912  n renv.= 87999912087999912 ppté: True
n= 21999999999999978  4n= 87999999999999912  n renv.= 87999999999999912 ppté: True
Nb chiffres: 18
n= 217800000000002178  4n= 871200000000008712  n renv.= 871200000000008712 ppté: True
n= 217800021780002178  4n= 871200087120008712  n renv.= 871200087120008712 ppté: True
n= 217800219978002178  4n= 871200879912008712  n renv.= 871200879912008712 ppté: True
n= 217802178217802178  4n= 871208712871208712  n renv.= 871208712871208712 ppté: True
n= 217802199997802178  4n= 871208799991208712  n renv.= 871208799991208712 ppté: True
n= 217821780021782178  4n= 871287120087128712  n renv.= 871287120087128712 ppté: True
n= 217821978219782178  4n= 871287912879128712  n renv.= 871287912879128712 ppté: True
n= 217821999999782178  4n= 871287999999128712  n renv.= 871287999999128712 ppté: True
n= 219780000000021978  4n= 879120000000087912  n renv.= 879120000000087912 ppté: True
n= 219780021780021978  4n= 879120087120087912  n renv.= 879120087120087912 ppté: True
n= 219780219978021978  4n= 879120879912087912  n renv.= 879120879912087912 ppté: True
n= 219782178217821978  4n= 879128712871287912  n renv.= 879128712871287912 ppté: True
n= 219782199997821978  4n= 879128799991287912  n renv.= 879128799991287912 ppté: True
n= 219978000000219978  4n= 879912000000879912  n renv.= 879912000000879912 ppté: True
n= 219978021780219978  4n= 879912087120879912  n renv.= 879912087120879912 ppté: True
n= 219978219978219978  4n= 879912879912879912  n renv.= 879912879912879912 ppté: True
n= 219997800002199978  4n= 879991200008799912  n renv.= 879991200008799912 ppté: True
n= 219997821782199978  4n= 879991287128799912  n renv.= 879991287128799912 ppté: True
n= 219999780021999978  4n= 879999120087999912  n renv.= 879999120087999912 ppté: True
n= 219999978219999978  4n= 879999912879999912  n renv.= 879999912879999912 ppté: True
n= 219999999999999978  4n= 879999999999999912  n renv.= 879999999999999912 ppté: True
Nb chiffres: 19
n= 2178000000000002178  4n= 8712000000000008712  n renv.= 8712000000000008712 ppté: True
n= 2178000219780002178  4n= 8712000879120008712  n renv.= 8712000879120008712 ppté: True
n= 2178002199978002178  4n= 8712008799912008712  n renv.= 8712008799912008712 ppté: True
n= 2178021780217802178  4n= 8712087120871208712  n renv.= 8712087120871208712 ppté: True
n= 2178021999997802178  4n= 8712087999991208712  n renv.= 8712087999991208712 ppté: True
n= 2178217800021782178  4n= 8712871200087128712  n renv.= 8712871200087128712 ppté: True
n= 2178219780219782178  4n= 8712879120879128712  n renv.= 8712879120879128712 ppté: True
n= 2178219999999782178  4n= 8712879999999128712  n renv.= 8712879999999128712 ppté: True
n= 2197800000000021978  4n= 8791200000000087912  n renv.= 8791200000000087912 ppté: True
n= 2197800219780021978  4n= 8791200879120087912  n renv.= 8791200879120087912 ppté: True
n= 2197802199978021978  4n= 8791208799912087912  n renv.= 8791208799912087912 ppté: True
n= 2197821780217821978  4n= 8791287120871287912  n renv.= 8791287120871287912 ppté: True
n= 2197821999997821978  4n= 8791287999991287912  n renv.= 8791287999991287912 ppté: True
n= 2199780000000219978  4n= 8799120000000879912  n renv.= 8799120000000879912 ppté: True
n= 2199780219780219978  4n= 8799120879120879912  n renv.= 8799120879120879912 ppté: True
n= 2199782199978219978  4n= 8799128799912879912  n renv.= 8799128799912879912 ppté: True
n= 2199978000002199978  4n= 8799912000008799912  n renv.= 8799912000008799912 ppté: True
n= 2199978219782199978  4n= 8799912879128799912  n renv.= 8799912879128799912 ppté: True
n= 2199997800021999978  4n= 8799991200087999912  n renv.= 8799991200087999912 ppté: True
n= 2199999780219999978  4n= 8799999120879999912  n renv.= 8799999120879999912 ppté: True
n= 2199999999999999978  4n= 8799999999999999912  n renv.= 8799999999999999912 ppté: True
Nb chiffres: 20
n= 21780000000000002178  4n= 87120000000000008712  n renv.= 87120000000000008712 ppté: True
n= 21780000217800002178  4n= 87120000871200008712  n renv.= 87120000871200008712 ppté: True
n= 21780002199780002178  4n= 87120008799120008712  n renv.= 87120008799120008712 ppté: True
n= 21780021782178002178  4n= 87120087128712008712  n renv.= 87120087128712008712 ppté: True
n= 21780021999978002178  4n= 87120087999912008712  n renv.= 87120087999912008712 ppté: True
n= 21780217800217802178  4n= 87120871200871208712  n renv.= 87120871200871208712 ppté: True
n= 21780219782197802178  4n= 87120879128791208712  n renv.= 87120879128791208712 ppté: True
n= 21780219999997802178  4n= 87120879999991208712  n renv.= 87120879999991208712 ppté: True
n= 21782178000021782178  4n= 87128712000087128712  n renv.= 87128712000087128712 ppté: True
n= 21782178217821782178  4n= 87128712871287128712  n renv.= 87128712871287128712 ppté: True
n= 21782197800219782178  4n= 87128791200879128712  n renv.= 87128791200879128712 ppté: True
n= 21782199782199782178  4n= 87128799128799128712  n renv.= 87128799128799128712 ppté: True
n= 21782199999999782178  4n= 87128799999999128712  n renv.= 87128799999999128712 ppté: True
n= 21978000000000021978  4n= 87912000000000087912  n renv.= 87912000000000087912 ppté: True
n= 21978000217800021978  4n= 87912000871200087912  n renv.= 87912000871200087912 ppté: True
n= 21978002199780021978  4n= 87912008799120087912  n renv.= 87912008799120087912 ppté: True
n= 21978021782178021978  4n= 87912087128712087912  n renv.= 87912087128712087912 ppté: True
n= 21978021999978021978  4n= 87912087999912087912  n renv.= 87912087999912087912 ppté: True
n= 21978217800217821978  4n= 87912871200871287912  n renv.= 87912871200871287912 ppté: True
n= 21978219782197821978  4n= 87912879128791287912  n renv.= 87912879128791287912 ppté: True
n= 21978219999997821978  4n= 87912879999991287912  n renv.= 87912879999991287912 ppté: True
n= 21997800000000219978  4n= 87991200000000879912  n renv.= 87991200000000879912 ppté: True
n= 21997800217800219978  4n= 87991200871200879912  n renv.= 87991200871200879912 ppté: True
n= 21997802199780219978  4n= 87991208799120879912  n renv.= 87991208799120879912 ppté: True
n= 21997821782178219978  4n= 87991287128712879912  n renv.= 87991287128712879912 ppté: True
n= 21997821999978219978  4n= 87991287999912879912  n renv.= 87991287999912879912 ppté: True
n= 21999780000002199978  4n= 87999120000008799912  n renv.= 87999120000008799912 ppté: True
n= 21999780217802199978  4n= 87999120871208799912  n renv.= 87999120871208799912 ppté: True
n= 21999782199782199978  4n= 87999128799128799912  n renv.= 87999128799128799912 ppté: True
n= 21999978000021999978  4n= 87999912000087999912  n renv.= 87999912000087999912 ppté: True
n= 21999978217821999978  4n= 87999912871287999912  n renv.= 87999912871287999912 ppté: True
n= 21999997800219999978  4n= 87999991200879999912  n renv.= 87999991200879999912 ppté: True
n= 21999999782199999978  4n= 87999999128799999912  n renv.= 87999999128799999912 ppté: True
n= 21999999999999999978  4n= 87999999999999999912  n renv.= 87999999999999999912 ppté: True
Nb chiffres: 21
n= 217800000000000002178  4n= 871200000000000008712  n renv.= 871200000000000008712 ppté: True
n= 217800002197800002178  4n= 871200008791200008712  n renv.= 871200008791200008712 ppté: True
n= 217800021999780002178  4n= 871200087999120008712  n renv.= 871200087999120008712 ppté: True
n= 217800217802178002178  4n= 871200871208712008712  n renv.= 871200871208712008712 ppté: True
n= 217800219999978002178  4n= 871200879999912008712  n renv.= 871200879999912008712 ppté: True
n= 217802178000217802178  4n= 871208712000871208712  n renv.= 871208712000871208712 ppté: True
n= 217802197802197802178  4n= 871208791208791208712  n renv.= 871208791208791208712 ppté: True
n= 217802199999997802178  4n= 871208799999991208712  n renv.= 871208799999991208712 ppté: True
n= 217821780000021782178  4n= 871287120000087128712  n renv.= 871287120000087128712 ppté: True
n= 217821782197821782178  4n= 871287128791287128712  n renv.= 871287128791287128712 ppté: True
n= 217821978000219782178  4n= 871287912000879128712  n renv.= 871287912000879128712 ppté: True
n= 217821997802199782178  4n= 871287991208799128712  n renv.= 871287991208799128712 ppté: True
n= 217821999999999782178  4n= 871287999999999128712  n renv.= 871287999999999128712 ppté: True
n= 219780000000000021978  4n= 879120000000000087912  n renv.= 879120000000000087912 ppté: True
n= 219780002197800021978  4n= 879120008791200087912  n renv.= 879120008791200087912 ppté: True
n= 219780021999780021978  4n= 879120087999120087912  n renv.= 879120087999120087912 ppté: True
n= 219780217802178021978  4n= 879120871208712087912  n renv.= 879120871208712087912 ppté: True
n= 219780219999978021978  4n= 879120879999912087912  n renv.= 879120879999912087912 ppté: True
n= 219782178000217821978  4n= 879128712000871287912  n renv.= 879128712000871287912 ppté: True
n= 219782197802197821978  4n= 879128791208791287912  n renv.= 879128791208791287912 ppté: True
n= 219782199999997821978  4n= 879128799999991287912  n renv.= 879128799999991287912 ppté: True
n= 219978000000000219978  4n= 879912000000000879912  n renv.= 879912000000000879912 ppté: True
n= 219978002197800219978  4n= 879912008791200879912  n renv.= 879912008791200879912 ppté: True
n= 219978021999780219978  4n= 879912087999120879912  n renv.= 879912087999120879912 ppté: True
n= 219978217802178219978  4n= 879912871208712879912  n renv.= 879912871208712879912 ppté: True
n= 219978219999978219978  4n= 879912879999912879912  n renv.= 879912879999912879912 ppté: True
n= 219997800000002199978  4n= 879991200000008799912  n renv.= 879991200000008799912 ppté: True
n= 219997802197802199978  4n= 879991208791208799912  n renv.= 879991208791208799912 ppté: True
n= 219997821999782199978  4n= 879991287999128799912  n renv.= 879991287999128799912 ppté: True
n= 219999780000021999978  4n= 879999120000087999912  n renv.= 879999120000087999912 ppté: True
n= 219999782197821999978  4n= 879999128791287999912  n renv.= 879999128791287999912 ppté: True
n= 219999978000219999978  4n= 879999912000879999912  n renv.= 879999912000879999912 ppté: True
n= 219999997802199999978  4n= 879999991208799999912  n renv.= 879999991208799999912 ppté: True
n= 219999999999999999978  4n= 879999999999999999912  n renv.= 879999999999999999912 ppté: True
Nb chiffres: 22
n= 2178000000000000002178  4n= 8712000000000000008712  n renv.= 8712000000000000008712 ppté: True
n= 2178000002178000002178  4n= 8712000008712000008712  n renv.= 8712000008712000008712 ppté: True
n= 2178000021997800002178  4n= 8712000087991200008712  n renv.= 8712000087991200008712 ppté: True
n= 2178000217821780002178  4n= 8712000871287120008712  n renv.= 8712000871287120008712 ppté: True
n= 2178000219999780002178  4n= 8712000879999120008712  n renv.= 8712000879999120008712 ppté: True
n= 2178002178002178002178  4n= 8712008712008712008712  n renv.= 8712008712008712008712 ppté: True
n= 2178002197821978002178  4n= 8712008791287912008712  n renv.= 8712008791287912008712 ppté: True
n= 2178002199999978002178  4n= 8712008799999912008712  n renv.= 8712008799999912008712 ppté: True
n= 2178021780000217802178  4n= 8712087120000871208712  n renv.= 8712087120000871208712 ppté: True
n= 2178021782178217802178  4n= 8712087128712871208712  n renv.= 8712087128712871208712 ppté: True
n= 2178021978002197802178  4n= 8712087912008791208712  n renv.= 8712087912008791208712 ppté: True
n= 2178021997821997802178  4n= 8712087991287991208712  n renv.= 8712087991287991208712 ppté: True
n= 2178021999999997802178  4n= 8712087999999991208712  n renv.= 8712087999999991208712 ppté: True
n= 2178217800000021782178  4n= 8712871200000087128712  n renv.= 8712871200000087128712 ppté: True
n= 2178217802178021782178  4n= 8712871208712087128712  n renv.= 8712871208712087128712 ppté: True
n= 2178217821997821782178  4n= 8712871287991287128712  n renv.= 8712871287991287128712 ppté: True
n= 2178219780000219782178  4n= 8712879120000879128712  n renv.= 8712879120000879128712 ppté: True
n= 2178219782178219782178  4n= 8712879128712879128712  n renv.= 8712879128712879128712 ppté: True
n= 2178219978002199782178  4n= 8712879912008799128712  n renv.= 8712879912008799128712 ppté: True
n= 2178219997821999782178  4n= 8712879991287999128712  n renv.= 8712879991287999128712 ppté: True
n= 2178219999999999782178  4n= 8712879999999999128712  n renv.= 8712879999999999128712 ppté: True
n= 2197800000000000021978  4n= 8791200000000000087912  n renv.= 8791200000000000087912 ppté: True
n= 2197800002178000021978  4n= 8791200008712000087912  n renv.= 8791200008712000087912 ppté: True
n= 2197800021997800021978  4n= 8791200087991200087912  n renv.= 8791200087991200087912 ppté: True
n= 2197800217821780021978  4n= 8791200871287120087912  n renv.= 8791200871287120087912 ppté: True
n= 2197800219999780021978  4n= 8791200879999120087912  n renv.= 8791200879999120087912 ppté: True
n= 2197802178002178021978  4n= 8791208712008712087912  n renv.= 8791208712008712087912 ppté: True
n= 2197802197821978021978  4n= 8791208791287912087912  n renv.= 8791208791287912087912 ppté: True
n= 2197802199999978021978  4n= 8791208799999912087912  n renv.= 8791208799999912087912 ppté: True
n= 2197821780000217821978  4n= 8791287120000871287912  n renv.= 8791287120000871287912 ppté: True
n= 2197821782178217821978  4n= 8791287128712871287912  n renv.= 8791287128712871287912 ppté: True
n= 2197821978002197821978  4n= 8791287912008791287912  n renv.= 8791287912008791287912 ppté: True
n= 2197821997821997821978  4n= 8791287991287991287912  n renv.= 8791287991287991287912 ppté: True
n= 2197821999999997821978  4n= 8791287999999991287912  n renv.= 8791287999999991287912 ppté: True
n= 2199780000000000219978  4n= 8799120000000000879912  n renv.= 8799120000000000879912 ppté: True
n= 2199780002178000219978  4n= 8799120008712000879912  n renv.= 8799120008712000879912 ppté: True
n= 2199780021997800219978  4n= 8799120087991200879912  n renv.= 8799120087991200879912 ppté: True
n= 2199780217821780219978  4n= 8799120871287120879912  n renv.= 8799120871287120879912 ppté: True
n= 2199780219999780219978  4n= 8799120879999120879912  n renv.= 8799120879999120879912 ppté: True
n= 2199782178002178219978  4n= 8799128712008712879912  n renv.= 8799128712008712879912 ppté: True
n= 2199782197821978219978  4n= 8799128791287912879912  n renv.= 8799128791287912879912 ppté: True
n= 2199782199999978219978  4n= 8799128799999912879912  n renv.= 8799128799999912879912 ppté: True
n= 2199978000000002199978  4n= 8799912000000008799912  n renv.= 8799912000000008799912 ppté: True
n= 2199978002178002199978  4n= 8799912008712008799912  n renv.= 8799912008712008799912 ppté: True
n= 2199978021997802199978  4n= 8799912087991208799912  n renv.= 8799912087991208799912 ppté: True
n= 2199978217821782199978  4n= 8799912871287128799912  n renv.= 8799912871287128799912 ppté: True
n= 2199978219999782199978  4n= 8799912879999128799912  n renv.= 8799912879999128799912 ppté: True
n= 2199997800000021999978  4n= 8799991200000087999912  n renv.= 8799991200000087999912 ppté: True
n= 2199997802178021999978  4n= 8799991208712087999912  n renv.= 8799991208712087999912 ppté: True
n= 2199997821997821999978  4n= 8799991287991287999912  n renv.= 8799991287991287999912 ppté: True
n= 2199999780000219999978  4n= 8799999120000879999912  n renv.= 8799999120000879999912 ppté: True
n= 2199999782178219999978  4n= 8799999128712879999912  n renv.= 8799999128712879999912 ppté: True
n= 2199999978002199999978  4n= 8799999912008799999912  n renv.= 8799999912008799999912 ppté: True
n= 2199999997821999999978  4n= 8799999991287999999912  n renv.= 8799999991287999999912 ppté: True
n= 2199999999999999999978  4n= 8799999999999999999912  n renv.= 8799999999999999999912 ppté: True
Nb chiffres: 23
n= 21780000000000000002178  4n= 87120000000000000008712  n renv.= 87120000000000000008712 ppté: True
n= 21780000021978000002178  4n= 87120000087912000008712  n renv.= 87120000087912000008712 ppté: True
n= 21780000219997800002178  4n= 87120000879991200008712  n renv.= 87120000879991200008712 ppté: True
n= 21780002178021780002178  4n= 87120008712087120008712  n renv.= 87120008712087120008712 ppté: True
n= 21780002199999780002178  4n= 87120008799999120008712  n renv.= 87120008799999120008712 ppté: True
n= 21780021780002178002178  4n= 87120087120008712008712  n renv.= 87120087120008712008712 ppté: True
n= 21780021978021978002178  4n= 87120087912087912008712  n renv.= 87120087912087912008712 ppté: True
n= 21780021999999978002178  4n= 87120087999999912008712  n renv.= 87120087999999912008712 ppté: True
n= 21780217800000217802178  4n= 87120871200000871208712  n renv.= 87120871200000871208712 ppté: True
n= 21780217821978217802178  4n= 87120871287912871208712  n renv.= 87120871287912871208712 ppté: True
n= 21780219780002197802178  4n= 87120879120008791208712  n renv.= 87120879120008791208712 ppté: True
n= 21780219978021997802178  4n= 87120879912087991208712  n renv.= 87120879912087991208712 ppté: True
n= 21780219999999997802178  4n= 87120879999999991208712  n renv.= 87120879999999991208712 ppté: True
n= 21782178000000021782178  4n= 87128712000000087128712  n renv.= 87128712000000087128712 ppté: True
n= 21782178021978021782178  4n= 87128712087912087128712  n renv.= 87128712087912087128712 ppté: True
n= 21782178219997821782178  4n= 87128712879991287128712  n renv.= 87128712879991287128712 ppté: True
n= 21782197800000219782178  4n= 87128791200000879128712  n renv.= 87128791200000879128712 ppté: True
n= 21782197821978219782178  4n= 87128791287912879128712  n renv.= 87128791287912879128712 ppté: True
n= 21782199780002199782178  4n= 87128799120008799128712  n renv.= 87128799120008799128712 ppté: True
n= 21782199978021999782178  4n= 87128799912087999128712  n renv.= 87128799912087999128712 ppté: True
n= 21782199999999999782178  4n= 87128799999999999128712  n renv.= 87128799999999999128712 ppté: True
n= 21978000000000000021978  4n= 87912000000000000087912  n renv.= 87912000000000000087912 ppté: True
n= 21978000021978000021978  4n= 87912000087912000087912  n renv.= 87912000087912000087912 ppté: True
n= 21978000219997800021978  4n= 87912000879991200087912  n renv.= 87912000879991200087912 ppté: True
n= 21978002178021780021978  4n= 87912008712087120087912  n renv.= 87912008712087120087912 ppté: True
n= 21978002199999780021978  4n= 87912008799999120087912  n renv.= 87912008799999120087912 ppté: True
n= 21978021780002178021978  4n= 87912087120008712087912  n renv.= 87912087120008712087912 ppté: True
n= 21978021978021978021978  4n= 87912087912087912087912  n renv.= 87912087912087912087912 ppté: True
n= 21978021999999978021978  4n= 87912087999999912087912  n renv.= 87912087999999912087912 ppté: True
n= 21978217800000217821978  4n= 87912871200000871287912  n renv.= 87912871200000871287912 ppté: True
n= 21978217821978217821978  4n= 87912871287912871287912  n renv.= 87912871287912871287912 ppté: True
n= 21978219780002197821978  4n= 87912879120008791287912  n renv.= 87912879120008791287912 ppté: True
n= 21978219978021997821978  4n= 87912879912087991287912  n renv.= 87912879912087991287912 ppté: True
n= 21978219999999997821978  4n= 87912879999999991287912  n renv.= 87912879999999991287912 ppté: True
n= 21997800000000000219978  4n= 87991200000000000879912  n renv.= 87991200000000000879912 ppté: True
n= 21997800021978000219978  4n= 87991200087912000879912  n renv.= 87991200087912000879912 ppté: True
n= 21997800219997800219978  4n= 87991200879991200879912  n renv.= 87991200879991200879912 ppté: True
n= 21997802178021780219978  4n= 87991208712087120879912  n renv.= 87991208712087120879912 ppté: True
n= 21997802199999780219978  4n= 87991208799999120879912  n renv.= 87991208799999120879912 ppté: True
n= 21997821780002178219978  4n= 87991287120008712879912  n renv.= 87991287120008712879912 ppté: True
n= 21997821978021978219978  4n= 87991287912087912879912  n renv.= 87991287912087912879912 ppté: True
n= 21997821999999978219978  4n= 87991287999999912879912  n renv.= 87991287999999912879912 ppté: True
n= 21999780000000002199978  4n= 87999120000000008799912  n renv.= 87999120000000008799912 ppté: True
n= 21999780021978002199978  4n= 87999120087912008799912  n renv.= 87999120087912008799912 ppté: True
n= 21999780219997802199978  4n= 87999120879991208799912  n renv.= 87999120879991208799912 ppté: True
n= 21999782178021782199978  4n= 87999128712087128799912  n renv.= 87999128712087128799912 ppté: True
n= 21999782199999782199978  4n= 87999128799999128799912  n renv.= 87999128799999128799912 ppté: True
n= 21999978000000021999978  4n= 87999912000000087999912  n renv.= 87999912000000087999912 ppté: True
n= 21999978021978021999978  4n= 87999912087912087999912  n renv.= 87999912087912087999912 ppté: True
n= 21999978219997821999978  4n= 87999912879991287999912  n renv.= 87999912879991287999912 ppté: True
n= 21999997800000219999978  4n= 87999991200000879999912  n renv.= 87999991200000879999912 ppté: True
n= 21999997821978219999978  4n= 87999991287912879999912  n renv.= 87999991287912879999912 ppté: True
n= 21999999780002199999978  4n= 87999999120008799999912  n renv.= 87999999120008799999912 ppté: True
n= 21999999978021999999978  4n= 87999999912087999999912  n renv.= 87999999912087999999912 ppté: True
n= 21999999999999999999978  4n= 87999999999999999999912  n renv.= 87999999999999999999912 ppté: True

