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.

A302220 Number of nX4 0..1 arrays with every element equal to 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 2
2 45
3 164
4 934
5 4237
6 21777
7 105585
8 523414
9 2578424
10 12726069
11 62802085
12 309849336
13 1529212139
14 7545987106
15 37239443170
16 183771070484
17 906898467298
18 4475474508545
19 22086156194245
20 108993766999235
21 537877222587527

List of values

[2, 45, 164, 934, 4237, 21777, 105585, 523414, 2578424, 12726069, 62802085, 309849336, 1529212139, 7545987106, 37239443170, 183771070484, 906898467298, 4475474508545, 22086156194245, 108993766999235, 537877222587527]

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

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