A108130 Partial sums of A108129.

2, 3, 5, 6, 7, 9, 12, 13, 15, 16, 17, 21, 24, 25, 29, 30, 32, 34, 35, 38, 40, 47, 48, 52, 53, 54, 56, 57, 58, 70, 73, 75, 79, 84, 85, 87, 94, 95, 97, 98, 101, 103, 108, 109, 113, 114, 117, 119, 120, 121, 131, 134, 136, 146, 155, 157, 165, 166, 167, 179, 180

Offset: 1

Author

Jorge Coveiro, Jun 04 2005

Keywords

• nonn

Crossrefs

Cf. A108129.

Programs

PARI

f(n) = my(k=2*n-1, m=1); while(!isprime(k*2^m-1), m++); m; \\ A108129
a(n) = sum(k=1, n, a(k));

Extensions

a(14) and following corrected by Georg Fischer, Dec 26 2022

Offset 1 from Michel Marcus, Dec 26 2022