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.

A239995 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4.

Table of values

n a(n)
1 3
2 13
3 61
4 256
5 1117
6 5012
7 22592
8 102336
9 465662
10 2123857
11 9698188
12 44317651
13 202610817
14 926532786
15 4237612923
16 19382872561
17 88661747469
18 405570672096
19 1855255219753
20 8486814865920
21 38822908166872
22 177595801954595

List of values

[3, 13, 61, 256, 1117, 5012, 22592, 102336, 465662, 2123857, 9698188, 44317651, 202610817, 926532786, 4237612923, 19382872561, 88661747469, 405570672096, 1855255219753, 8486814865920, 38822908166872, 177595801954595]

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

Content is available under The OEIS End-User License Agreement.