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.

A140526 Number of derangements of n elements with one pair repeated exactly once (e.g., "ABABCDEF").

Table of values

n a(n)
4 1
5 4
6 29
7 230
8 2033
9 19744
10 209581
11 2418226
12 30173825
13 405194012
14 5830108061
15 89520810334
16 1461569944369
17 25288635875320
18 462312939395693
19 8905623605897834
20 180313351427440001
21 3828575562533760436

List of values

[1, 4, 29, 230, 2033, 19744, 209581, 2418226, 30173825, 405194012, 5830108061, 89520810334, 1461569944369, 25288635875320, 462312939395693, 8905623605897834, 180313351427440001, 3828575562533760436]

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

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