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.

A145867 Number of involutions of length 2n which are invariant under the reverse-complement map and have no decreasing subsequence of length 7.

Table of values

n a(n)
0 1
1 2
2 6
3 20
4 74
5 292
6 1214
7 5252
8 23468
9 107672
10 505048
11 2413776
12 11723188
13 57737032
14 287853518
15 1450697572
16 7381645844
17 37884748712
18 195947389208
19 1020610698832
20 5349968198328
21 28208066576176
22 149526042974008
23 796520870628752
24 4262367319460848

List of values

[1, 2, 6, 20, 74, 292, 1214, 5252, 23468, 107672, 505048, 2413776, 11723188, 57737032, 287853518, 1450697572, 7381645844, 37884748712, 195947389208, 1020610698832, 5349968198328, 28208066576176, 149526042974008, 796520870628752, 4262367319460848]

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

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