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.

A303521 Number of nX4 0..1 arrays with every element equal to 0, 1, 3, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 5
2 21
3 37
4 103
5 340
6 1115
7 4112
8 16640
9 71025
10 320957
11 1510853
12 7287031
13 35723065
14 176869202
15 880763327
16 4401181230
17 22037652351
18 110478062574
19 554227859714
20 2781487076749
21 13962670138510
22 70100301160570
23 351970530142109

List of values

[5, 21, 37, 103, 340, 1115, 4112, 16640, 71025, 320957, 1510853, 7287031, 35723065, 176869202, 880763327, 4401181230, 22037652351, 110478062574, 554227859714, 2781487076749, 13962670138510, 70100301160570, 351970530142109]

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

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