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.

A190917 Number of permutations of n copies of 1..3 introduced in order 1..3 with no element equal to another within a distance of 1.

Table of values

n a(n)
0 1
1 1
2 5
3 29
4 182
5 1198
6 8142
7 56620
8 400598
9 2872754
10 20824778
11 152303410
12 1122149800
13 8319825040
14 62017475600
15 464452683432
16 3492568119566
17 26358270711370
18 199565061455634
19 1515311001158482
20 11535716330003876
21 88025068713285476
22 673124069796140900

List of values

[1, 1, 5, 29, 182, 1198, 8142, 56620, 400598, 2872754, 20824778, 152303410, 1122149800, 8319825040, 62017475600, 464452683432, 3492568119566, 26358270711370, 199565061455634, 1515311001158482, 11535716330003876, 88025068713285476, 673124069796140900]

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

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