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.

A286973 Number of n X 2 0..1 arrays with the number of 1's horizontally or vertically adjacent to some 0 two less than the number of 0's adjacent to some 1.

Table of values

n a(n)
1 0
2 0
3 5
4 30
5 126
6 520
7 2088
8 8192
9 32083
10 125728
11 492331
12 1927334
13 7545086
14 29542032
15 115713230
16 453479812
17 1778221568
18 6976989468
19 27390464896
20 107590106636
21 422842742731
22 1662688326476
23 6541232413273
24 25746371202362
25 101384373381977
26 399406874608396
27 1574130883669277

List of values

[0, 0, 5, 30, 126, 520, 2088, 8192, 32083, 125728, 492331, 1927334, 7545086, 29542032, 115713230, 453479812, 1778221568, 6976989468, 27390464896, 107590106636, 422842742731, 1662688326476, 6541232413273, 25746371202362, 101384373381977, 399406874608396, 1574130883669277]

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

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