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.

A302266 Number of 2Xn 0..1 arrays with every element equal to 0, 1, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 2
2 8
3 29
4 105
5 384
6 1405
7 5135
8 18766
9 68589
10 250693
11 916272
12 3348929
13 12240187
14 44737350
15 163513041
16 597632937
17 2184322000
18 7983600501
19 29179707415
20 106650542494
21 389803024901
22 1424712848861
23 5207262571120
24 19032314831801

List of values

[2, 8, 29, 105, 384, 1405, 5135, 18766, 68589, 250693, 916272, 3348929, 12240187, 44737350, 163513041, 597632937, 2184322000, 7983600501, 29179707415, 106650542494, 389803024901, 1424712848861, 5207262571120, 19032314831801]

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

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