A355962 - OEIS

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A355962

Primes p such that (p+7)^(p-1) == 1 (mod p^2).

6

2, 3, 229, 701, 31446553, 1016476523, 8918351831

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OFFSET

1,1

COMMENTS

a(8) > 10^13 if it exists. - Jason Yuen, May 12 2024

Equivalently, primes p such that 7^p == p+7 (mod p^2), or Fermat quotient q_p(7) == 1/7 (mod p). - Max Alekseyev, Sep 16 2024

LINKS

Table of n, a(n) for n=1..7.

PROG

(PARI) forprime(p=1, , if(Mod(p+7, p^2)^(p-1)==1, print1(p, ", ")))

CROSSREFS

(p+k)^(p-1) == 1 (mod p^2): A355959 (k=2), A355960 (k=5), A355961 (k=6), A355963 (k=8), A355964 (k=9), A355965 (k=10).

Sequence in context: A037275 A142960 A117324 * A037059 A302398 A087313

Adjacent sequences: A355959 A355960 A355961 * A355963 A355964 A355965

KEYWORD

nonn,hard,more

AUTHOR

Felix Fröhlich, Jul 21 2022

EXTENSIONS

a(7) from Jason Yuen, May 12 2024

STATUS

approved