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.

A240762 Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero 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 4
2 12
3 19
4 142
5 553
6 4112
7 18373
8 131958
9 625820
10 4472258
11 21760942
12 154039075
13 763999159
14 5342021291
15 26913960199
16 185826785482
17 949177894331
18 6473768540990
19 33478372193270
20 225722723781992
21 1180496482754391

List of values

[4, 12, 19, 142, 553, 4112, 18373, 131958, 625820, 4472258, 21760942, 154039075, 763999159, 5342021291, 26913960199, 185826785482, 949177894331, 6473768540990, 33478372193270, 225722723781992, 1180496482754391]