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.

A177543 Number of permutations of {1,...,n} avoiding adjacent step pattern up, down, up, down, up, down.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 24
5 120
6 720
7 4768
8 35968
9 312064
10 3004160
11 31764480
12 365798400
13 4555499520
14 61232590848
15 882227765248
16 13547017240576
17 221038858829824
18 3818608204709888
19 69637156745773056
20 1336921845773107200
21 26947721453843251200
22 569023211226594803712

List of values

[1, 1, 2, 6, 24, 120, 720, 4768, 35968, 312064, 3004160, 31764480, 365798400, 4555499520, 61232590848, 882227765248, 13547017240576, 221038858829824, 3818608204709888, 69637156745773056, 1336921845773107200, 26947721453843251200, 569023211226594803712]

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

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