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.

A208528 Number of permutations of n>1 having exactly 3 points P on the boundary of their bounding square.

Table of values

n a(n)
2 0
3 4
4 16
5 72
6 384
7 2400
8 17280
9 141120
10 1290240
11 13063680
12 145152000
13 1756339200
14 22992076800
15 323805081600
16 4881984307200
17 78460462080000
18 1339058552832000
19 24186745110528000
20 460970906812416000
21 9245027631071232000
22 194632160654131200000

List of values

[0, 4, 16, 72, 384, 2400, 17280, 141120, 1290240, 13063680, 145152000, 1756339200, 22992076800, 323805081600, 4881984307200, 78460462080000, 1339058552832000, 24186745110528000, 460970906812416000, 9245027631071232000, 194632160654131200000]

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

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