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.

A240150 Number of nX4 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.

Table of values

n a(n)
1 7
2 19
3 107
4 676
5 3993
6 22412
7 131005
8 731518
9 4144347
10 23263202
11 131973267
12 742448151
13 4200516883
14 23673251649
15 133792056873
16 754644250144
17 4262766555182
18 24053911144152
19 135834058269434
20 766651910127519

List of values

[7, 19, 107, 676, 3993, 22412, 131005, 731518, 4144347, 23263202, 131973267, 742448151, 4200516883, 23673251649, 133792056873, 754644250144, 4262766555182, 24053911144152, 135834058269434, 766651910127519]