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A128165
Numbers k such that k divides 1 plus the sum of the first k primes.
93
1, 2, 6, 10, 20, 22, 28, 155, 488, 664, 992, 6162, 7840, 7975, 8793, 18961, 32422, 148220, 231625, 332198, 459121, 462932, 2115894, 8108930, 10336641, 11789731, 15500046, 23483195, 46571611, 48582404, 77033887, 105390951, 132421841, 229481560, 1224959312
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OFFSET
1,2
COMMENTS
a(44) > 4.4*10^10. - Robert Price, Dec 15 2013
a(50) > 10^14. - Bruce Garner, Jun 05 2021
LINKS
Bruce Garner, Table of n, a(n) for n = 1..49
OEIS Wiki, Sums of powers of primes divisibility sequences
MATHEMATICA
k = 0; s = 1; p = 2; A128165 = {}; While[k < 247336000, If[Mod[s += p, ++k] == 0, AppendTo[A128165, k]; Print[{k, p}]]; p = NextPrime@ p]; A128165
PROG
(PARI) is(n)=sum(i=1, n, prime(i), 1)%n==0 \\ Charles R Greathouse IV, Nov 07 2014
(PARI) n=0; s=1; forprime(p=2, 1e9, s+=p; if(s%n++==0, print1(n", "))) \\ Charles R Greathouse IV, Nov 07 2014
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, A024450, A111441, A217599, A128166, A233862, A217600, A217601.
Sequence in context: A028247 A209535 A065054 * A097646 A077084 A239542
Adjacent sequences: A128162 A128163 A128164 * A128166 A128167 A128168
KEYWORD
hard,nonn
AUTHOR
Alexander Adamchuk, Feb 22 2007
EXTENSIONS
More terms from Ryan Propper, Apr 05 2007
a(34) from Robert G. Wilson v, Jan 21 2011
a(35) from Robert Price, Dec 15 2013
STATUS
approved

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Last modified November 7 02:29 EST 2024. Contains 377523 sequences.
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