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.

A295525 Number of n X 2 0..1 arrays with each 1 horizontally or vertically adjacent to 1, 2 or 4 1s.

Table of values

n a(n)
1 2
2 10
3 29
4 87
5 280
6 876
7 2735
8 8583
9 26900
10 84274
11 264107
12 827651
13 2593568
14 8127490
15 25469197
16 79812833
17 250109752
18 783769936
19 2456102483
20 7696696911
21 24119166438
22 75582316528
23 236852570799
24 742225734425
25 2325915393694
26 7288729246884

List of values

[2, 10, 29, 87, 280, 876, 2735, 8583, 26900, 84274, 264107, 827651, 2593568, 8127490, 25469197, 79812833, 250109752, 783769936, 2456102483, 7696696911, 24119166438, 75582316528, 236852570799, 742225734425, 2325915393694, 7288729246884]

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

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