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.

A196489 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,3,0,1,4 for x=0,1,2,3,4.

Table of values

n a(n)
1 1
2 5
3 23
4 99
5 435
6 1821
7 7761
8 33445
9 142899
10 610111
11 2610127
12 11166323
13 47747117
14 204171367
15 873175939
16 3734216551
17 15969151905
18 68291795495
19 292051077171
20 1248957218645
21 5341159082973
22 22841464889713
23 97681553556621

List of values

[1, 5, 23, 99, 435, 1821, 7761, 33445, 142899, 610111, 2610127, 11166323, 47747117, 204171367, 873175939, 3734216551, 15969151905, 68291795495, 292051077171, 1248957218645, 5341159082973, 22841464889713, 97681553556621]

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

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