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.

A303457 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 2, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 4
2 32
3 232
4 1690
5 12340
6 90112
7 658204
8 4807732
9 35118024
10 256519346
11 1873747524
12 13686804048
13 99975389852
14 730271188300
15 5334272943080
16 38964248230442
17 284614727917460
18 2078971032009920
19 15185864006789660
20 110925290484682724

List of values

[4, 32, 232, 1690, 12340, 90112, 658204, 4807732, 35118024, 256519346, 1873747524, 13686804048, 99975389852, 730271188300, 5334272943080, 38964248230442, 284614727917460, 2078971032009920, 15185864006789660, 110925290484682724]

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

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