A136369 Numbers k such that A136368(k) is prime.

2, 5, 6, 8, 18, 20, 98, 1863

Offset: 1

Author

Alexander Adamchuk, Dec 27 2007

Keywords

• nonn
• more

Crossrefs

Cf. A024530 (numerator of Sum_{k=1..n} (-1)^k / prime(k)).

Cf. A136368 (numerator of Sum_{k=1..n} (-1)^(k+1)/prime(k)^2).

Cf. A136365, A136366, A136367, A136370, A136371.

Programs

Mathematica

f=0; Do[ p=Prime[n]; f=f + (-1)^(n+1)*1/p^2; g=Numerator[f] ;If[ PrimeQ[g], Print[ {n, g} ] ], {n, 1, 100} ]

Extensions

a(8) from Robert Price, Aug 28 2019