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.

A177478 Permutations avoiding the consecutive patterns 4312 and 4213.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 22
5 100
6 540
7 3388
8 24248
9 195048
10 1742860
11 17127880
12 183617280
13 2132433940
14 26669752928
15 357375269160
16 5108084756320
17 77574769941760
18 1247401873186560
19 21172559509803520
20 378282904982091200
21 7096584257305845120
22 139471475802695196160

List of values

[1, 1, 2, 6, 22, 100, 540, 3388, 24248, 195048, 1742860, 17127880, 183617280, 2132433940, 26669752928, 357375269160, 5108084756320, 77574769941760, 1247401873186560, 21172559509803520, 378282904982091200, 7096584257305845120, 139471475802695196160]

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

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