A125707 Numbers k such that A024528(k) is prime.

1, 2, 3, 4, 5, 7, 14, 15, 17, 23, 32, 36, 42, 309, 1384, 1588, 5631, 11226

Offset

1,2

Links

Table of n, a(n) for n=1..18.

Mathematica

f=1; Do[p=Prime[n]; f=f+1/p; g=Numerator[f]; If[PrimeQ[g], Print[{n, p, g}]], {n, 1, 50}]

Crossrefs

Cf. A024528, A109628.

Sequence in context: A268199 A178767 A337188 * A039060 A278442 A092065

Adjacent sequences: A125704 A125705 A125706 * A125708 A125709 A125710

Keyword

nonn,hard,more

Author

Alexander Adamchuk, Feb 01 2007

Extensions

a(14)-a(16) from Ryan Propper, Feb 11 2008

a(17)-a(18) from Michael S. Branicky, Apr 27 2025

Status

approved