A338357 First differences of A283312.

1, 2, -1, 3, -1, 5, -3, 7, -6, 1, 2, 11, -10, 1, 13, -11, 1, 1, 17, -16, 1, 19, -18, 1, 2, 23, -22, 1, 2, 1, 1, 29, -28, 1, 31, -30, 1, 2, 1, 1, 37, -35, 1, 1, 41, -40, 1, 43, -42, 1, 2, 47, -46, 1, 1, 1, 1, 1, 53, -52, 1, 1, 1, 2, 59, -58, 1, 61, -59, 1, 1, 1, 1, 67, -66, 1, 1, 1, 71

Offset: 1

Author

N. J. A. Sloane, Nov 03 2020

Keywords

• sign

Links

• N. J. A. Sloane, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A283312.

Programs

Mathematica

Module[{nmax = 100, smn = 1}, Differences[Nest[Append[#, If[PrimeQ[Last[#]], 2*Last[#], While[MemberQ[#, ++smn]]; smn]]&, {1}, nmax]]] (* Paolo Xausa, Feb 12 2024 *)