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.

A177536 Number of permutations of {1,...,n} avoiding adjacent step pattern up, down, down, down, up, down.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 24
5 120
6 720
7 4962
8 39072
9 346032
10 3404160
11 36853442
12 435133488
13 5566069380
14 76676528112
15 1131700250442
16 17817052536384
17 298034349244128
18 5278625637077376
19 98686282426953080
20 1942087278998014400
21 40130098178033129036
22 868710371909527352944

List of values

[1, 1, 2, 6, 24, 120, 720, 4962, 39072, 346032, 3404160, 36853442, 435133488, 5566069380, 76676528112, 1131700250442, 17817052536384, 298034349244128, 5278625637077376, 98686282426953080, 1942087278998014400, 40130098178033129036, 868710371909527352944]

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

Content is available under The OEIS End-User License Agreement.