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.

A269109 T(n,k)=Number of nXk 0..3 arrays with some element plus some horizontally or vertically adjacent neighbor totalling three no more than once.

Table of values

n a(n)
1 4
2 16
3 16
4 60
5 180
6 60
7 216
8 1740
9 1740
10 216
11 756
12 15540
13 40908
14 15540
15 756
16 2592
17 132300
18 872460
19 872460
20 132300
21 2592
22 8748
23 1090740
24 17593092
25 43964700
26 17593092
27 1090740
28 8748
29 29160
30 8787660
31 342055548
32 2085484068
33 2085484068

List of values

[4, 16, 16, 60, 180, 60, 216, 1740, 1740, 216, 756, 15540, 40908, 15540, 756, 2592, 132300, 872460, 872460, 132300, 2592, 8748, 1090740, 17593092, 43964700, 17593092, 1090740, 8748, 29160, 8787660, 342055548, 2085484068, 2085484068]

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

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