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A233040 Prime(n), where n is such that (1+sum_{i=1..n} prime(i)^7) / n is an integer. 1
2, 3, 7, 11, 13, 29, 37, 199, 15679, 18211, 59359, 78203, 84533, 166399, 528299, 639697, 2080651, 2914033, 5687413, 73463179, 112760273, 156196991, 278840981, 503948113, 3706314893, 3786209711, 12626179519, 13551633533, 13844655553, 24074338279, 37937104823 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(36) > 1066173339601.

LINKS

Robert Price, Table of n, a(n) for n = 1..35

OEIS Wiki, Sums of powers of primes divisibility sequences

EXAMPLE

a(4) = 11, because 11 is the 5th prime and the sum of the first 5 primes^7+1 = 20391155 when divided by 5 equals 4078231 which is an integer.

MATHEMATICA

t = {}; sm = 1; Do[sm = sm + Prime[n]^7; If[Mod[sm, n] == 0, AppendTo[t, Prime[n]]], {n, 100000}]; t (* Derived from A217599 *)

PROG

(PARI) is(n)=if(!isprime(n), return(0)); my(t=primepi(n), s); forprime(p=2, n, s+=Mod(p, t)^7); s==0 \\ Charles R Greathouse IV, Nov 30 2013

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: A233414 A233863 A233194 * A233769 A038895 A291657

Adjacent sequences:  A233037 A233038 A233039 * A233041 A233042 A233043

KEYWORD

nonn

AUTHOR

Robert Price, Dec 03 2013

STATUS

approved

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Last modified February 22 15:05 EST 2020. Contains 332137 sequences. (Running on oeis4.)