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A232770
Prime(k), where k is such that (Sum_{i=1..k} prime(i)^13) / k is an integer.
0
2, 83, 1979, 2081, 2326469, 6356923, 7170679, 63812027, 4652001719, 241949473277, 163220642765623, 1260677492111911, 8150959175977039
OFFSET
1,1
COMMENTS
a(13) > 1352363608564489. - Bruce Garner, Aug 30 2021
a(14) > 18205684894350047. - Paul W. Dyson, Dec 06 2024
EXAMPLE
a(2) = 83, because 83 is the 23rd prime and the sum of the first 23 primes^13 = 17226586990098074754709144 when divided by 23 equals 748982043047742380639528 which is an integer.
MATHEMATICA
t = {}; sm = 0; Do[sm = sm + Prime[n]^13; 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)^13); 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).
Sequence in context: A065591 A266201 A225807 * A317724 A099373 A169601
KEYWORD
nonn,more
AUTHOR
Robert Price, Nov 29 2013
EXTENSIONS
a(11) from Bruce Garner, Mar 23 2021
a(12) from Bruce Garner, Aug 30 2021
a(13) from Paul W. Dyson, Apr 20 2023
STATUS
approved