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.

A144086 Number of partial bijections (or subpermutations) of an n-element set with exactly 1 fixed point.

Table of values

n a(n)
0 0
1 1
2 2
3 12
4 72
5 540
6 4680
7 46200
8 510720
9 6244560
10 83613600
11 1216131840
12 19084222080
13 321271030080
14 5773503415680
15 110288062684800
16 2231100039168000
17 47640952315756800
18 1070630750168179200
19 25255541547460224000
20 623884298434645248000
21 16104652019138319436800

List of values

[0, 1, 2, 12, 72, 540, 4680, 46200, 510720, 6244560, 83613600, 1216131840, 19084222080, 321271030080, 5773503415680, 110288062684800, 2231100039168000, 47640952315756800, 1070630750168179200, 25255541547460224000, 623884298434645248000, 16104652019138319436800]

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

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