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.

A231971 Number of (n+1) X (2+1) 0..1 arrays with no element having a strict majority of its horizontal and vertical neighbors equal to one.

Table of values

n a(n)
1 16
2 56
3 169
4 550
5 1764
6 5680
7 18225
8 58596
9 188356
10 605458
11 1946025
12 6255180
13 20106256
14 64627982
15 207734569
16 667725402
17 2146283584
18 6898841796
19 22175081569
20 71277802674
21 229109651716
22 736431677100
23 2367126871209
24 7608702637640

List of values

[16, 56, 169, 550, 1764, 5680, 18225, 58596, 188356, 605458, 1946025, 6255180, 20106256, 64627982, 207734569, 667725402, 2146283584, 6898841796, 22175081569, 71277802674, 229109651716, 736431677100, 2367126871209, 7608702637640]

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

Content is available under The OEIS End-User License Agreement.