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.

A094047 Number of seating arrangements of n couples around a round table (up to rotations) so that each person sits between two people of the opposite sex and no couple is seated together.

Table of values

n a(n)
1 0
2 0
3 2
4 12
5 312
6 9600
7 416880
8 23879520
9 1749363840
10 159591720960
11 17747520940800
12 2363738855385600
13 371511874881100800
14 68045361697964851200
15 14367543450324474009600
16 3464541314885011705344000
17 946263209467217020194816000
18 290616691739323132839591936000

List of values

[0, 0, 2, 12, 312, 9600, 416880, 23879520, 1749363840, 159591720960, 17747520940800, 2363738855385600, 371511874881100800, 68045361697964851200, 14367543450324474009600, 3464541314885011705344000, 946263209467217020194816000, 290616691739323132839591936000]

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

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