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.

A303526 Number of 3Xn 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 4
2 6
3 18
4 37
5 80
6 286
7 916
8 2532
9 7477
10 24285
11 76820
12 235117
13 731307
14 2316410
15 7294592
16 22810317
17 71569571
18 225378484
19 708826544
20 2225946457
21 6995090976
22 21998860077
23 69164809009
24 217385283885
25 683342646350
26 2148402980261

List of values

[4, 6, 18, 37, 80, 286, 916, 2532, 7477, 24285, 76820, 235117, 731307, 2316410, 7294592, 22810317, 71569571, 225378484, 708826544, 2225946457, 6995090976, 21998860077, 69164809009, 217385283885, 683342646350, 2148402980261]

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

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