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A241913
Complement of A241912, natural numbers not fixed by A241916.
4
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
1,1
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
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 *)
PROG
(Scheme, with Antti Karttunen's IntSeq-library)
(define A241913 (COMPLEMENT 1 A241912))
CROSSREFS
Complement of A241912.
A subsequence apart from its two initial terms: A088902.
Cf. A241916.
Sequence in context: A325229 A036347 A129492 * A053869 A085275 A177201
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 03 2014
STATUS
approved