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.

A267903 Number of 3Xn arrays containing n copies of 0..3-1 with every element equal to at least one horizontal or vertical neighbor and the top left element equal to 0.

Table of values

n a(n)
1 0
2 6
3 20
4 268
5 2324
6 28318
7 315196
8 3786836
9 45099306
10 547824556
11 6687936028
12 82350672500
13 1019550923830
14 12691867518330
15 158695413996448
16 1992293553570646
17 25099547132728742
18 317210539882144928

List of values

[0, 6, 20, 268, 2324, 28318, 315196, 3786836, 45099306, 547824556, 6687936028, 82350672500, 1019550923830, 12691867518330, 158695413996448, 1992293553570646, 25099547132728742, 317210539882144928]

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

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