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.

A246073 Number of permutations p on [2n] satisfying p^n(i) = i for all i in [n].

Table of values

n a(n)
0 1
1 1
2 10
3 108
4 6672
5 109200
6 45007920
7 983324160
8 665546434560
9 60174422501760
10 32648180513760000
11 4656975300322329600
12 13859947861644771532800
13 1193599114668580293273600
14 1257285172911535450293811200
15 766119340152013216053484800000

List of values

[1, 1, 10, 108, 6672, 109200, 45007920, 983324160, 665546434560, 60174422501760, 32648180513760000, 4656975300322329600, 13859947861644771532800, 1193599114668580293273600, 1257285172911535450293811200, 766119340152013216053484800000]

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

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