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.

A177483 Number of permutations of n avoiding the pattern 1231'.

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 20
5 85
6 420
7 2443
8 16136
9 120222
10 993770
11 9042451
12 89725944
13 964693717
14 11168801294
15 138549935190
16 1833264311504
17 25773751694161
18 383664263687964
19 6028473673565695
20 99710105438401940
21 1731651866118338766
22 31505416776034601510
23 599259743707431667279

List of values

[1, 1, 2, 6, 20, 85, 420, 2443, 16136, 120222, 993770, 9042451, 89725944, 964693717, 11168801294, 138549935190, 1833264311504, 25773751694161, 383664263687964, 6028473673565695, 99710105438401940, 1731651866118338766, 31505416776034601510, 599259743707431667279]

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

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