A076291 a(n) = A002977(n+1) - A002977(n).

2, 1, 3, 2, 1, 3, 2, 4, 2, 1, 5, 1, 3, 8, 1, 3, 2, 1, 9, 2, 1, 5, 1, 3, 12, 2, 1, 3, 2, 4, 2, 1, 17, 4, 2, 1, 3, 6, 2, 1, 5, 1, 3, 20, 4, 2, 1, 5, 1, 3, 8, 4, 2, 1, 3, 9, 21, 8, 4, 2, 1, 5, 1, 3, 8, 1, 3, 2, 1, 9, 2, 1, 5, 1, 3, 36, 8, 4, 2, 1, 9, 2, 1, 5, 1, 3, 9, 3, 8, 4, 2, 1, 5, 1, 3, 14, 1, 3, 9, 29, 16

Offset: 1

Author

Benoit Cloitre, Nov 06 2002

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000
• Benoit Cloitre, Illustration of initial terms

Crossrefs

Cf. A002977.

Programs

Mathematica

seq[max_] := Module[{s = Flatten[NestWhileList[Flatten[{2*# + 1, 3*# + 1}] &, 1, Min[#1] < max &]]}, Differences[Union[Select[s, # <= max &]]]]; seq[400000] (* Amiram Eldar, May 07 2022 *)