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.

A288910 Number of permutations p of [n] such that 0p has a nonincreasing up-jump sequence and also has a nonincreasing down-jump sequence.

Table of values

n a(n)
0 1
1 1
2 2
3 5
4 18
5 69
6 303
7 1357
8 6552
9 31961
10 163587
11 839710
12 4485686
13 23917300
14 131366017
15 722130351
16 4059017880
17 22809880116
18 130713878478
19 748596353814
20 4354695496124
21 25349532110660
22 149415724294027
23 881419904003486
24 5256588077063477
25 31377362011756061

List of values

[1, 1, 2, 5, 18, 69, 303, 1357, 6552, 31961, 163587, 839710, 4485686, 23917300, 131366017, 722130351, 4059017880, 22809880116, 130713878478, 748596353814, 4354695496124, 25349532110660, 149415724294027, 881419904003486, 5256588077063477, 31377362011756061]

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

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