cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A128170 Numbers k such that k divides 1 + Sum_{j=1..k} prime(j)^6.

Original entry on oeis.org

1, 2, 3, 4, 6, 7, 8, 9, 12, 14, 18, 21, 24, 27, 28, 29, 34, 36, 42, 45, 48, 54, 56, 63, 72, 84, 112, 126, 159, 168, 174, 198, 204, 216, 252, 310, 312, 336, 360, 400, 408, 441, 504, 505, 540, 588, 591, 657, 672, 716, 864, 900, 1080, 1152, 1316, 1350, 1380, 1680, 1722
Offset: 1

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Author

Alexander Adamchuk, Feb 22 2007

Keywords

Comments

a(301) > 1.4*10^13. - Bruce Garner, Apr 07 2021

Crossrefs

Cf. A085450 (smallest m > 1 such that m divides Sum_{k=1..m} prime(k)^n).

Programs

  • Mathematica
    s = 1; Do[s = s + Prime[n]^6; If[ Mod[s, n] == 0, Print[n]], {n, 10000}]
    Module[{nn=1750,pr},pr=Accumulate[Prime[Range[nn]]^6];Select[Thread[ {Range[ nn],pr}],Divisible[#[[2]]+1,#[[1]]]&]][[All,1]] (* Harvey P. Dale, Feb 10 2019 *)
  • PARI
    n=0; s=1; forprime(p=2,,s+=p^6; if(s%n++==0, print1(n", "))) \\ Charles R Greathouse IV, Dec 03 2013