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.

A208143 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.

Table of values

n a(n)
1 8
2 64
3 240
4 900
5 2400
6 6400
7 14000
8 30625
9 58800
10 112896
11 197568
12 345744
13 564480
14 921600
15 1425600
16 2205225
17 3267000
18 4840000
19 6921200
20 9897316
21 13741728
22 19079424
23 25836720
24 34987225
25 46373600
26 61465600
27 79968000
28 104040000

List of values

[8, 64, 240, 900, 2400, 6400, 14000, 30625, 58800, 112896, 197568, 345744, 564480, 921600, 1425600, 2205225, 3267000, 4840000, 6921200, 9897316, 13741728, 19079424, 25836720, 34987225, 46373600, 61465600, 79968000, 104040000]