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.

A321273 Sum over all permutations of [n] of the maximum of the lengths of increasing or decreasing subsequences.

Table of values

n a(n)
1 1
2 4
3 14
4 70
5 396
6 2628
7 20270
8 175392
9 1686374
10 17920528
11 208454628
12 2629931688
13 35774761662
14 522351495684
15 8149929922408
16 135284126840592
17 2380119357533974
18 44243729657494640
19 866599471539160876
20 17839886344238238784
21 385065445154671172880
22 8695565142604747421416

List of values

[1, 4, 14, 70, 396, 2628, 20270, 175392, 1686374, 17920528, 208454628, 2629931688, 35774761662, 522351495684, 8149929922408, 135284126840592, 2380119357533974, 44243729657494640, 866599471539160876, 17839886344238238784, 385065445154671172880, 8695565142604747421416]

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

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