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

Author

Pontus von Brömssen, Sep 08 2022

Keywords

• nonn

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

Crossrefs

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

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).