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.

A183304 Half the number of n X 3 binary arrays with no element equal to a strict majority of its horizontal and vertical neighbors.

Table of values

n a(n)
1 1
2 4
3 9
4 19
5 42
6 93
7 205
8 452
9 997
10 2199
11 4850
12 10697
13 23593
14 52036
15 114769
16 253131
17 558298
18 1231365
19 2715861
20 5990020
21 13211405
22 29138671
23 64267362
24 141746129
25 312630929
26 689529220
27 1520804569
28 3354240067
29 7398009354
30 16316823277

List of values

[1, 4, 9, 19, 42, 93, 205, 452, 997, 2199, 4850, 10697, 23593, 52036, 114769, 253131, 558298, 1231365, 2715861, 5990020, 13211405, 29138671, 64267362, 141746129, 312630929, 689529220, 1520804569, 3354240067, 7398009354, 16316823277]

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

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