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.

A222900 Number of nX2 0..3 arrays with no more than floor(nX2/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

Table of values

n a(n)
1 1
2 4
3 14
4 75
5 411
6 2522
7 15919
8 103627
9 683480
10 4554799
11 30542304
12 205785953
13 1391485044
14 9436529666
15 64150640719
16 437015936703
17 2982527052975
18 20387828050502
19 139566607631735
20 956650211233825
21 6564964362464004

List of values

[1, 4, 14, 75, 411, 2522, 15919, 103627, 683480, 4554799, 30542304, 205785953, 1391485044, 9436529666, 64150640719, 437015936703, 2982527052975, 20387828050502, 139566607631735, 956650211233825, 6564964362464004]

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

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