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.

A300461 Number of nX4 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 0
2 4
3 8
4 28
5 142
6 540
7 2585
8 11343
9 51501
10 233028
11 1052448
12 4769842
13 21579345
14 97715668
15 442378911
16 2002838338
17 9067930634
18 41054700887
19 185876096558
20 841553822832
21 3810142997823
22 17250454214015
23 78101569076062

List of values

[0, 4, 8, 28, 142, 540, 2585, 11343, 51501, 233028, 1052448, 4769842, 21579345, 97715668, 442378911, 2002838338, 9067930634, 41054700887, 185876096558, 841553822832, 3810142997823, 17250454214015, 78101569076062]

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

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