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A125826 Numbers m such that m divides 2^7 + 3^7 + 5^7 + ... + prime(m)^7. 2
1, 25, 1677, 21875, 538513, 1015989, 18522325, 1130976595, 1721158369, 561122374231, 1763726985077, 2735295422833, 7631117283951 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A232865 for prime(a(n)). - M. F. Hasler, Dec 01 2013

a(14) > 10^13. - Bruce Garner, Mar 23 2021

LINKS

Table of n, a(n) for n=1..13.

OEIS Wiki, Sums of powers of primes divisibility sequences.

MATHEMATICA

s = 0; Do[s = s + Prime[n]^7; If[ Mod[s, n] == 0, Print[n]], {n, 25000}]

PROG

(PARI) s=0; n=0; forprime(p=2, 4e9, s+=p^7; if(s%n++==0, print1(n", "))) \\ Charles R Greathouse IV, Mar 16 2011

CROSSREFS

Cf. A085450 = smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n.

Cf. A007504, A045345, A171399, A128165, A233523, A050247, A050248.

Cf. A024450, A111441, A217599, A128166, A233862, A217600, A217601.

Sequence in context: A196299 A196217 A196684 * A263967 A290881 A316911

Adjacent sequences:  A125823 A125824 A125825 * A125827 A125828 A125829

KEYWORD

hard,nonn

AUTHOR

Alexander Adamchuk, Feb 03 2007

EXTENSIONS

More terms from Ryan Propper, Mar 26 2007

a(8)-a(9) from Charles R Greathouse IV, Mar 16 2011

a(10) from Paul W. Dyson, Jan 05 2021

a(11)-a(12) from Bruce Garner, Feb 26 2021

a(13) from Bruce Garner, Mar 23 2021

STATUS

approved

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Last modified May 11 13:41 EDT 2021. Contains 343791 sequences. (Running on oeis4.)