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.

A258666 A total of n married couples, including a mathematician M and his wife, are to be seated at the 2n chairs around a circular table, with no man seated next to his wife. After the ladies are seated at every other chair, M is the first man allowed to choose one of the remaining chairs. The sequence gives the number of ways of seating the other men, with no man seated next to his wife, if M chooses the chair that is 7 seats clockwise from his wife's chair.

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 4
6 20
7 117
8 791
9 6204
10 55004
11 543595
12 5922925
13 70518884
14 910711076
15 12678337153
16 189252394275
17 3015217877068
18 51067618521276
19 916176420499159
20 17355904074255065
21 346195849623668420
22 7252654428822549364
23 159210363264445218829
24 3654550887654460566191

List of values

[0, 0, 0, 0, 4, 20, 117, 791, 6204, 55004, 543595, 5922925, 70518884, 910711076, 12678337153, 189252394275, 3015217877068, 51067618521276, 916176420499159, 17355904074255065, 346195849623668420, 7252654428822549364, 159210363264445218829, 3654550887654460566191]

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

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