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.

A302118 Number of permutations p of [n] such that |p(i) - p(i-1)| is in {1,3} for all i from 2 to n.

Table of values

n a(n)
0 1
1 1
2 2
3 2
4 8
5 12
6 32
7 40
8 88
9 118
10 244
11 338
12 642
13 912
14 1650
15 2402
16 4182
17 6200
18 10492
19 15786
20 26166
21 39814
22 64994
23 99738
24 161020
25 248670
26 398248
27 617912
28 983890
29 1531796
30 2428988
31 3790980
32 5993746
33 9371174
34 14785512
35 23146268
36 36465816
37 57137316
38 89924384

List of values

[1, 1, 2, 2, 8, 12, 32, 40, 88, 118, 244, 338, 642, 912, 1650, 2402, 4182, 6200, 10492, 15786, 26166, 39814, 64994, 99738, 161020, 248670, 398248, 617912, 983890, 1531796, 2428988, 3790980, 5993746, 9371174, 14785512, 23146268, 36465816, 57137316, 89924384]

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

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