cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A064636 Number of derangements up to cyclic rotations; permutation siteswap necklaces, with no fixed points (no "zero-throws", i.e., empty hands, if we use the mapping Perm2SiteSwap1 of A060495 and A060498).

Table of values

n a(n)
0 0
1 0
2 1
3 2
4 5
5 12
6 55
7 270
8 1893
9 14864
10 133749
11 1334970
12 14687195
13 176214852
14 2290820923
15 32071104006
16 481066907653
17 7697064251760
18 130850098582189
19 2355301661033970
20 44750731672347273
21 895014631193654828
22 18795307257304746591
23 413496759611120779902
24 9510425471105377569963
25 228250211305338670543432

List of values

[0, 0, 1, 2, 5, 12, 55, 270, 1893, 14864, 133749, 1334970, 14687195, 176214852, 2290820923, 32071104006, 481066907653, 7697064251760, 130850098582189, 2355301661033970, 44750731672347273, 895014631193654828, 18795307257304746591, 413496759611120779902, 9510425471105377569963, 228250211305338670543432]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.