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.

A302640 Number of 7Xn 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 64
2 86
3 189
4 657
5 2303
6 8981
7 30216
8 112431
9 408512
10 1512824
11 5441957
12 20021696
13 73157743
14 268090840
15 977883198
16 3582780118
17 13103336584
18 47949599697
19 175342870194
20 641714970276
21 2347546538523
22 8589020632731
23 31421666502319

List of values

[64, 86, 189, 657, 2303, 8981, 30216, 112431, 408512, 1512824, 5441957, 20021696, 73157743, 268090840, 977883198, 3582780118, 13103336584, 47949599697, 175342870194, 641714970276, 2347546538523, 8589020632731, 31421666502319]

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

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