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.

A321278 One half of the sum over all permutations of [n] of the squared difference between the length of the longest increasing subsequence and the length of the longest decreasing subsequence.

Table of values

n a(n)
1 0
2 1
3 4
4 18
5 105
6 699
7 5285
8 45128
9 431223
10 4540775
11 52268029
12 653096124
13 8810538490
14 127622293057
15 1975379879871
16 32537074533872
17 568268861724191
18 10490690233451583
19 204118868130889733
20 4174977363687339452
21 89554055679215605982
22 2010207472655266461533

List of values

[0, 1, 4, 18, 105, 699, 5285, 45128, 431223, 4540775, 52268029, 653096124, 8810538490, 127622293057, 1975379879871, 32537074533872, 568268861724191, 10490690233451583, 204118868130889733, 4174977363687339452, 89554055679215605982, 2010207472655266461533]

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

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