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.

A239839 Number of ordered pairs of permutation functions on n elements satisfying f(f(f(x))) = g(f(g(x))).

Table of values

n a(n)
0 1
1 1
2 4
3 18
4 168
5 1560
6 20880
7 267120
8 5080320
9 93623040
10 2184537600
11 49896000000
12 1451853849600
13 41739720422400
14 1426847092070400
15 47989033956864000
16 1919268439216128000
17 76229151152394240000
18 3471527082588364800000
19 156226856133456396288000

List of values

[1, 1, 4, 18, 168, 1560, 20880, 267120, 5080320, 93623040, 2184537600, 49896000000, 1451853849600, 41739720422400, 1426847092070400, 47989033956864000, 1919268439216128000, 76229151152394240000, 3471527082588364800000, 156226856133456396288000]

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

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