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.

A145846 Number of permutations of length 2n which are invariant under the reverse-complement map and have no decreasing subsequences of length 6.

Table of values

n a(n)
0 1
1 2
2 8
3 47
4 357
5 3270
6 34515
7 406460
8 5215829
9 71677058
10 1041363040
11 15841778155
12 250494079945
13 4093630537014
14 68830515423498
15 1186424966652225
16 20902566718237725
17 375485138838707850
18 6863181435514906992
19 127420716337372828539
20 2399321143670605041105

List of values

[1, 2, 8, 47, 357, 3270, 34515, 406460, 5215829, 71677058, 1041363040, 15841778155, 250494079945, 4093630537014, 68830515423498, 1186424966652225, 20902566718237725, 375485138838707850, 6863181435514906992, 127420716337372828539, 2399321143670605041105]

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

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