A117988 Number of functions f:[n]->[n] such that f[(x^2) mod n]=[f(x)^2] mod n for all x in [n], for n=1,2,3,... Here [n] denotes {0,1,2,...,n-1}.

1, 4, 6, 16, 18, 576, 78, 1728, 1365, 5184, 486, 2985984, 3474, 389376, 13583700, 268435456, 65538, 119246400, 45006, 39261044736, 21400013700, 15116544, 67590, 45476068117708800, 8696104065, 772395264, 19496328075, 1822309056774144, 231340050

Offset: 1

Author

John W. Layman, Apr 14 2006

Keywords

• nonn

Comments

See A117986 and A117987 for results on other modular functional equations.

Links

• Rémy Sigrist, Table of n, a(n) for n = 1..767
• Rémy Sigrist, PARI program for A117988

Crossrefs

Cf. A023153, A117986, A117987.

Programs

PARI

\\ See Links section.

Extensions

More terms from Rémy Sigrist, Sep 20 2019