A077126 Sum of even-indexed primes.

3, 10, 23, 42, 71, 108, 151, 204, 265, 336, 415, 504, 605, 712, 825, 956, 1095, 1246, 1409, 1582, 1763, 1956, 2155, 2378, 2607, 2846, 3097, 3360, 3631, 3912, 4205, 4516, 4833, 5170, 5519, 5878, 6251, 6634, 7031, 7440, 7861, 8294, 8737, 9194, 9657, 10136, 10627

Offset: 1

Author

Jon Perry, Nov 29 2002

Keywords

• nonn

Comments

Partial sums of A031215. - Michel Marcus, Oct 27 2015

Examples

			p_1=2, p_2=3, p_3=5 and p_4=7, therefore a(2) = p_2 + p_4 = 3 + 7 = 10.
		

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A031215, A077131.

Programs

Mathematica

A077126list[nmax_]:=Accumulate[Prime[Range[2,2nmax,2]]];A077126list[100] (* Paolo Xausa, Aug 28 2023 *)

PARI

pc=1; ps=0; forprime (p=2,500,pc=3-pc; if (pc==1,ps=ps+p; print1(ps",")))