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.

A132647 Number of permutations of [n] having no substring [k,k+1,k+2,k+3].

Table of values

n a(n)
0 1
1 1
2 2
3 6
4 23
5 117
6 706
7 4962
8 39817
9 359171
10 3597936
11 39630372
12 476066277
13 6194080387
14 86776390796
15 1302376048620
16 20847721870931
17 354549730559949
18 6384006047649910
19 121330369923079290
20 2427196999663678987
21 50981866833670160201
22 1121806937829102793662

List of values

[1, 1, 2, 6, 23, 117, 706, 4962, 39817, 359171, 3597936, 39630372, 476066277, 6194080387, 86776390796, 1302376048620, 20847721870931, 354549730559949, 6384006047649910, 121330369923079290, 2427196999663678987, 50981866833670160201, 1121806937829102793662]

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

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