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.

A232956 Number of 2 X n 0..3 arrays with no element x(i,j) adjacent to value 3-x(i,j) horizontally, diagonally or antidiagonally, and top left element zero.

Table of values

n a(n)
1 4
2 21
3 129
4 771
5 4629
6 27771
7 166629
8 999771
9 5998629
10 35991771
11 215950629
12 1295703771
13 7774222629
14 46645335771
15 279872014629
16 1679232087771
17 10075392526629
18 60452355159771
19 362714130958629
20 2176284785751771

List of values

[4, 21, 129, 771, 4629, 27771, 166629, 999771, 5998629, 35991771, 215950629, 1295703771, 7774222629, 46645335771, 279872014629, 1679232087771, 10075392526629, 60452355159771, 362714130958629, 2176284785751771]

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

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