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.

A205817 Number of (n+1) X 3 0..2 arrays with the number of clockwise edge increases in every 2 X 2 subblock unequal to the number of counterclockwise edge increases.

Table of values

n a(n)
1 66
2 216
3 714
4 2430
5 8274
6 28242
7 96402
8 329130
9 1123698
10 3836538
11 13098738
12 44721882
13 152690034
14 521316378
15 1779885426
16 6076908954
17 20747864946
18 70837641882
19 241854837618
20 825744066714
21 2819266591602
22 9625578232986

List of values

[66, 216, 714, 2430, 8274, 28242, 96402, 329130, 1123698, 3836538, 13098738, 44721882, 152690034, 521316378, 1779885426, 6076908954, 20747864946, 70837641882, 241854837618, 825744066714, 2819266591602, 9625578232986]

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

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