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.

A182540 Number of ways of arranging the numbers 1 through n on a circle so that no sum of two adjacent numbers is prime, up to rotations and reflections.

Table of values

n a(n)
1 0
2 0
3 0
4 0
5 0
6 1
7 6
8 44
9 208
10 912
11 8016
12 61952
13 671248
14 8160620
15 87412258
16 888954284
17 12156253488
18 180955852060
19 2907927356451
20 50317255621843
21 802326797235038
22 12251146829850324
23 233309934271940028
24 4243527581615332664
25 79533825261873435894
26 1602629887788636447221
27 30450585799991840921483
28 622433536382831426225696
29 14891218890120375419560713
30 344515231090957672408413959

List of values

[0, 0, 0, 0, 0, 1, 6, 44, 208, 912, 8016, 61952, 671248, 8160620, 87412258, 888954284, 12156253488, 180955852060, 2907927356451, 50317255621843, 802326797235038, 12251146829850324, 233309934271940028, 4243527581615332664, 79533825261873435894, 1602629887788636447221, 30450585799991840921483, 622433536382831426225696, 14891218890120375419560713, 344515231090957672408413959]

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

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