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A131263
Numbers k such that k divides 2^9 + 3^9 + 5^9 + ... + prime(k)^9.
2
1, 281525, 1011881, 13721649, 309777093, 417800903, 12252701193, 27377813605, 37762351523, 245773819141, 51230573255953, 82578361848569, 277900491430385
OFFSET
1,2
COMMENTS
a(12) > 5.5*10^13. - Paul W. Dyson, Mar 27 2021
a(13) > 10^14. - Bruce Garner, Jan 10 2022
a(14) > 3*10^14. - Paul W. Dyson, Aug 11 2022
MATHEMATICA
s = 0; Do[s = s + Prime[n]^9; If[ Mod[s, n] == 0, Print[n]], {n, 1100000}]
PROG
(PARI) s=0; n=0; forprime(p=2, 1e9, s+=p^9; if(s%n++==0, print1(n", "))) \\ Charles R Greathouse IV, Apr 14 2011
CROSSREFS
Cf. A085450 (smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n).
Sequence in context: A257151 A257158 A254740 * A235173 A245659 A321055
KEYWORD
nonn,more
AUTHOR
Alexander Adamchuk, Jun 25 2007, Jun 27 2007
EXTENSIONS
a(4) from Robert G. Wilson v, Jun 27 2007
a(5)-a(10) from Charles R Greathouse IV, Apr 14 2011
a(11) from Paul W. Dyson, Mar 27 2021
a(12) from Bruce Garner, Jan 10 2022
a(13) from Paul W. Dyson, Aug 11 2022
STATUS
approved