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.

A231581 Number of nX2 0..3 arrays with no element less than a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors.

Table of values

n a(n)
1 4
2 28
3 124
4 602
5 2776
6 12922
7 60720
8 286047
9 1335296
10 6256326
11 29377828
12 137595239
13 644951590
14 3024402309
15 14175895645
16 66459189937
17 311583082104
18 1460702584712
19 6848241858778
20 32106603868468
21 150524267596760
22 705711781367756

List of values

[4, 28, 124, 602, 2776, 12922, 60720, 286047, 1335296, 6256326, 29377828, 137595239, 644951590, 3024402309, 14175895645, 66459189937, 311583082104, 1460702584712, 6848241858778, 32106603868468, 150524267596760, 705711781367756]

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

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