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.

A222583 Number of nX3 0..2 arrays with no more than floor(nX3/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..2 order.

Table of values

n a(n)
1 1
2 5
3 9
4 112
5 426
6 4790
7 18007
8 208768
9 783389
10 9222742
11 34725955
12 412489970
13 1558983053
14 18631988604
15 70660866011
16 848302913944
17 3226795572945
18 38872008280152
19 148241838020273
20 1790674769103638
21 6843805534505557

List of values

[1, 5, 9, 112, 426, 4790, 18007, 208768, 783389, 9222742, 34725955, 412489970, 1558983053, 18631988604, 70660866011, 848302913944, 3226795572945, 38872008280152, 148241838020273, 1790674769103638, 6843805534505557]

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

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