A357004 Smallest k for which the cyclic Haar graphs with indices k and n are isomorphic.

1, 2, 3, 4, 5, 5, 7, 8, 9, 10, 11, 9, 11, 11, 15, 16, 17, 17, 19, 17, 19, 19, 23, 17, 19, 19, 23, 19, 23, 23, 31, 32, 33, 34, 35, 36, 37, 37, 39, 34, 37, 42, 43, 37, 45, 43, 47, 33, 35, 37, 39, 37, 43, 45, 47, 35, 39, 43, 47, 39, 47, 47, 63, 64, 65, 65, 67, 65

Offset

1,2

Comments

The fixed points are the terms of A137706.

The number of fixed points n in the interval 2^(m-1) <= n < 2^m equals A357000(m).

Links

Pontus von Brömssen, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Haar Graph

Formula

a(a(n)) = a(n).

a(n) = A357005(n) for n <= 146, but a(147) = 141 < 147 = A357005(147).

a(n) <= A357005(n) <= A163382(n).

Crossrefs

Cf. A137706 (fixed points; or ordered list of distinct terms), A163382, A272919 (terms that occur only once), A357000, A357005.

Sequence in context: A131233 A136623 A031218 * A357005 A267508 A163382

Adjacent sequences: A357001 A357002 A357003 * A357005 A357006 A357007

Keyword

nonn

Author

Pontus von Brömssen, Sep 08 2022

Status

approved