A337610 Positive integers m such that A126287^k(m) = m for some positive integer k.

1, 10, 15, 22, 26, 33, 34, 46, 51, 58, 65, 69, 70, 82, 86, 87, 94, 105, 106, 118, 122, 123, 130, 134, 141, 142, 146, 154, 159, 166, 177, 178, 190, 195, 202, 206, 213, 214, 215, 218, 226, 231, 238, 249, 250, 254, 262, 266, 267, 274, 285, 286, 298, 302, 303, 310

Offset

1,2

Comments

A126287^k(m) means apply A126287 to m k times.

Equivalently, the numbers that belong to a cycle under the map x -> A126287(x).

For any term m in this sequence, A126287(A126287(m)) = m.

Supersequence of A017641. Moreover, this sequence (excluding the first term) can be represented as an infinite union of arithmetic progressions.

There are no primes in this sequence.

Links

Ely Golden, Table of n, a(n) for n = 1..10000

Ely Golden, Python program for generating terms of this sequence

Example

10 is a term since A126287(A126287(10)) = A126287(15) = 10.

Crossrefs

Cf. A017641, A126287, A337609, A337611, A337612.

Sequence in context: A115682 A075523 A115679 * A109373 A373421 A267329

Adjacent sequences: A337607 A337608 A337609 * A337611 A337612 A337613

Keyword

nonn,easy

Author

Ely Golden, Oct 07 2020

Status

approved