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.

A328130 Number of n-bead necklace structures with beads of exactly four colors and no adjacent beads having the same color.

Table of values

n a(n)
1 0
2 0
3 0
4 1
5 1
6 5
7 10
8 33
9 83
10 237
11 640
12 1817
13 5005
14 14099
15 39504
16 111585
17 315235
18 894845
19 2544220
20 7256607
21 20738097
22 59405343
23 170488450
24 490221899
25 1411923987
26 4073098085
27 11767069378
28 34041318969
29 98603778565
30 285954140473
31 830194632190
32 2412764894021
33 7018972487319

List of values

[0, 0, 0, 1, 1, 5, 10, 33, 83, 237, 640, 1817, 5005, 14099, 39504, 111585, 315235, 894845, 2544220, 7256607, 20738097, 59405343, 170488450, 490221899, 1411923987, 4073098085, 11767069378, 34041318969, 98603778565, 285954140473, 830194632190, 2412764894021, 7018972487319]

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

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