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.

A239837 Number of ordered pairs of permutation functions on n elements satisfying f(f(x)) = g(f(g(x))).

Table of values

n a(n)
0 1
1 1
2 2
3 12
4 96
5 600
6 6480
7 85680
8 1048320
9 16692480
10 315705600
11 5468601600
12 117834393600
13 2951607859200
14 68958028339200
15 1856897602560000
16 58228124258304000
17 1721171464556544000
18 56379302852640768000
19 2111880588197732352000
20 76033053559536353280000

List of values

[1, 1, 2, 12, 96, 600, 6480, 85680, 1048320, 16692480, 315705600, 5468601600, 117834393600, 2951607859200, 68958028339200, 1856897602560000, 58228124258304000, 1721171464556544000, 56379302852640768000, 2111880588197732352000, 76033053559536353280000]

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

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