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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.

A371992 Number of different closest packings of equal spheres for rhombohedral crystals having repeat period n.

Table of values

n a(n)
1 0
2 0
3 1
4 1
5 2
6 3
7 5
8 8
9 15
10 23
11 41
12 70
13 126
14 223
15 406
16 740
17 1370
18 2545
19 4769
20 8977
21 16985
22 32261
23 61469
24 117488
25 225060
26 432159
27 831235
28 1601796
29 3090926
30 5973198
31 11556533
32 22385600
33 43405353
34 84247085
35 163661488
36 318209920
37 619181766
38 1205733457
39 2349558582
40 4581555964
41 8939468450
42 17453081143
43 34094082857

List of values

[0, 0, 1, 1, 2, 3, 5, 8, 15, 23, 41, 70, 126, 223, 406, 740, 1370, 2545, 4769, 8977, 16985, 32261, 61469, 117488, 225060, 432159, 831235, 1601796, 3090926, 5973198, 11556533, 22385600, 43405353, 84247085, 163661488, 318209920, 619181766, 1205733457, 2349558582, 4581555964, 8939468450, 17453081143, 34094082857]

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

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