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.

A302636 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 4
2 6
3 8
4 14
5 25
6 47
7 83
8 150
9 269
10 488
11 876
12 1581
13 2845
14 5133
15 9242
16 16661
17 30012
18 54094
19 97457
20 175631
21 316451
22 570258
23 1027529
24 1851592
25 3336392
26 6012049
27 10833241
28 19520945
29 35175378
30 63384029
31 114213840
32 205806518
33 370850169
34 668249367

List of values

[4, 6, 8, 14, 25, 47, 83, 150, 269, 488, 876, 1581, 2845, 5133, 9242, 16661, 30012, 54094, 97457, 175631, 316451, 570258, 1027529, 1851592, 3336392, 6012049, 10833241, 19520945, 35175378, 63384029, 114213840, 205806518, 370850169, 668249367]

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

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