A111318 Numbers k such that 4 divides prime(1) + ... + prime(k).

5, 9, 11, 15, 17, 19, 21, 25, 27, 29, 31, 33, 35, 37, 45, 49, 71, 79, 81, 83, 85, 87, 91, 95, 97, 99, 101, 103, 105, 107, 109, 111, 115, 117, 119, 121, 125, 129, 131, 135, 155, 159, 161, 163, 165, 169, 171, 173, 175, 177, 179, 181, 183, 185, 193, 195, 199, 201, 203, 205

Offset: 1

Author

N. J. A. Sloane, Nov 05 2005

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Harvey P. Dale)

Crossrefs

Cf. A007504, A103208, A111319, A111320, A111321, A111322, A111323, A111324, A111325, A111326, A111327.

Programs

Mathematica

Module[{nn=300,prs},prs=Accumulate[Prime[Range[nn]]];Select[Range[ nn], Divisible[prs[[#]],4]&]] (* Harvey P. Dale, May 27 2012 *)

PARI

lista(pmax) = {my(s = 0, k = 0); forprime(p = 2, pmax, k++; s += p; if(!(s % 4), print1(k, ", ")));} \\ Amiram Eldar, May 14 2024