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.

A299589 Number of n X n 0..1 arrays with every element unequal to 0, 1 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Table of values

n a(n)
1 1
2 1
3 5
4 23
5 113
6 576
7 2583
8 11656
9 54738
10 252959
11 1159927
12 5359097
13 24760544
14 114126327
15 526426848
16 2429504050
17 11207820807
18 51702119063
19 238537489057
20 1100501704736
21 5077031912807
22 23422773519432
23 108060889914594

List of values

[1, 1, 5, 23, 113, 576, 2583, 11656, 54738, 252959, 1159927, 5359097, 24760544, 114126327, 526426848, 2429504050, 11207820807, 51702119063, 238537489057, 1100501704736, 5077031912807, 23422773519432, 108060889914594]

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

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