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A233413
Numbers k such that k divides 1 + Sum_{j=1..k} prime(j)^15.
1
1, 2, 4, 5, 6, 10, 12, 14, 22, 74, 397, 524, 620, 857, 3727, 8171, 9194, 41032, 59604, 109471, 123231, 166394, 195736, 203440, 494620, 805738, 3000362, 6861264, 64286003, 69417562, 113888084, 162292604, 241184820, 658646484, 864667379, 1027008032, 4023976348
OFFSET
1,2
COMMENTS
a(49) > 2*10^13. - Bruce Garner, Jun 02 2021
LINKS
Bruce Garner, Table of n, a(n) for n = 1..48 (first 43 terms from Robert Price)
EXAMPLE
a(6)=10 because 1 plus the sum of the first 10 primes^15 is 8913922901063237276800 which is divisible by 10.
MATHEMATICA
p = 2; k = 0; s = 1; lst = {}; While[k < 40000000000, s = s + p^15; If[Mod[s, ++k] == 0, AppendTo[lst, k]; Print[{k, p}]]; p = NextPrime@ p] (* derived from A128169 *)
CROSSREFS
Cf. A085450 (smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n).
Sequence in context: A014871 A029513 A061949 * A128167 A364214 A162534
KEYWORD
nonn
AUTHOR
Robert Price, Dec 09 2013
STATUS
approved