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.

A240645 Number of nX4 0..1 arrays with no element equal to the same number of vertical neighbors as horizontal neighbors, with new values 0..1 introduced in row major order.

Table of values

n a(n)
1 2
2 3
3 8
4 18
5 61
6 168
7 526
8 1643
9 5524
10 18762
11 65149
12 228440
13 807770
14 2872483
15 10255424
16 36709394
17 131630309
18 472542776
19 1697728566
20 6102699043
21 21944561100
22 78928279002
23 283926402165
24 1021465508456
25 3675119389202
26 13223276351667

List of values

[2, 3, 8, 18, 61, 168, 526, 1643, 5524, 18762, 65149, 228440, 807770, 2872483, 10255424, 36709394, 131630309, 472542776, 1697728566, 6102699043, 21944561100, 78928279002, 283926402165, 1021465508456, 3675119389202, 13223276351667]

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

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