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A122004 Primes p that divide A123373(p-1). 1
2, 3, 5, 23, 29 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

A123373 begins {4, 48, 3598, 924780, 287358579128, ...}.

a(1) = 2 because 2 divides A123373(1) = 4.

a(2) = 3 because 3 divides A123373(2) = 48.

a(3) = 5 because 5 divides A123373(4) = 924780.

PROG

(PARI) is(p) = isprime(p) && sum(j=1, p-1, sum(k=1, p-1, Mod(prime(k), p)^prime(j))) == 0; \\ Jinyuan Wang, Jan 16 2021

(Python)

from sympy import nextprime, prime

p, A122004_list = 2, []

while p < 10**6:

    if 0 == sum(pow(prime(i), prime(j), p) for i in range(1, p) for j in range(1, p)) % p:

        A122004_list.append(p)

    p = nextprime(p) # Chai Wah Wu, Feb 19 2021

CROSSREFS

Cf. A086787, A123373.

Sequence in context: A024767 A041195 A042141 * A023231 A034470 A237812

Adjacent sequences:  A122001 A122002 A122003 * A122005 A122006 A122007

KEYWORD

nonn,more,hard

AUTHOR

Alexander Adamchuk, Oct 14 2006

STATUS

approved

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Last modified December 4 10:59 EST 2021. Contains 349486 sequences. (Running on oeis4.)