A241913 Complement of A241912, natural numbers not fixed by A241916.

6, 9, 10, 12, 14, 20, 21, 22, 24, 25, 26, 27, 28, 30, 33, 34, 35, 36, 38, 39, 40, 42, 44, 46, 48, 49, 51, 52, 54, 56, 57, 58, 60, 62, 63, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 99, 100, 102, 104, 106, 110, 111

Offset: 1

Author

Antti Karttunen, May 03 2014

Keywords

• nonn

Comments

Terms that occur in 2-cycles of permutation A241916. (E.g., A241916(6)=9, A241916(9)=6.)

Apart from its initial terms, 1 and 2, all the terms of A088902 occur here because A241909 has no other fixed points than 1 and 2.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Complement of A241912.

A subsequence apart from its two initial terms: A088902.

Cf. A241916.

Programs

Mathematica

f[n_] := If[n == 1, {0}, Function[f, ReplacePart[Table[0, {PrimePi[f[[-1, 1]]]}], #] &@ Map[PrimePi@ First@ # -> Last@ # &, f]]@ FactorInteger@ n]; g[w_List] := Times @@ Flatten@ MapIndexed[Prime[#2]^#1 &, w]; Complement[Range@ Max@ #, Table[#[[n + 1]]/2, {n, Length@ # - 1}]] &@ Select[Range@ 120, g@ f@ # == g@ Reverse@ f@ # &] (* Michael De Vlieger, Aug 27 2016 *)