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.

A268905 Number of 2 X n 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

Table of values

n a(n)
1 0
2 36
3 168
4 696
5 2664
6 9720
7 34344
8 118584
9 402408
10 1347192
11 4461480
12 14644152
13 47711592
14 154472184
15 497428776
16 1594323000
17 5089079016
18 16185567096
19 51311691432
20 162200044728
21 511395045480
22 1608569870328
23 5048863812648

List of values

[0, 36, 168, 696, 2664, 9720, 34344, 118584, 402408, 1347192, 4461480, 14644152, 47711592, 154472184, 497428776, 1594323000, 5089079016, 16185567096, 51311691432, 162200044728, 511395045480, 1608569870328, 5048863812648]

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

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