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A232848 Prime(n), where n is such that (sum_{i=1..n} prime(i)^15) / n is an integer. 0
2, 59, 97, 127, 12517, 54581, 83921, 89273, 1396411, 2562719, 4952183, 29201281, 35562101, 47567557, 111213143, 184201627, 1172476337, 7309217299, 287609314877 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(20) > 1093881323023.

LINKS

Table of n, a(n) for n=1..19.

OEIS Wiki, Sums of powers of primes divisibility sequences

FORMULA

a(n) = prime(A131275(n)).

EXAMPLE

a(2) = 59, because 59 is the 17th prime and the sum of the first 17 primes^15 = 455708280934100194626604550 when divided by 17 equals 26806369466711776154506150 which is an integer.

MATHEMATICA

t = {}; sm = 0; Do[sm = sm + Prime[n]^15; 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)^15); s==0 \\ Charles R Greathouse IV, Nov 30 2013

(PARI) S=n=0; forprime(p=1, , (S+=p^15)%n++||print1(p", ")) \\ - M. F. Hasler, Dec 01 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: A195325 A195329 A197185 * A215393 A141869 A329551

Adjacent sequences:  A232845 A232846 A232847 * A232849 A232850 A232851

KEYWORD

nonn,more

AUTHOR

Robert Price, Dec 09 2013

STATUS

approved

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Last modified July 15 04:34 EDT 2020. Contains 335763 sequences. (Running on oeis4.)