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.

A268633 Number of n X 2 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two exactly once.

Table of values

n a(n)
1 3
2 24
3 120
4 504
5 1944
6 7128
7 25272
8 87480
9 297432
10 997272
11 3306744
12 10865016
13 35429400
14 114791256
15 369882936
16 1186176312
17 3788111448
18 12053081880
19 38225488248
20 120875192568
21 381221761176
22 1199453833944
23 3765727153080

List of values

[3, 24, 120, 504, 1944, 7128, 25272, 87480, 297432, 997272, 3306744, 10865016, 35429400, 114791256, 369882936, 1186176312, 3788111448, 12053081880, 38225488248, 120875192568, 381221761176, 1199453833944, 3765727153080]

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

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