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.

A222373 Number of nX2 0..3 arrays with no more than floor(nX2/2) elements unequal to at least one horizontal or vertical neighbor, with new values introduced in row major 0..3 order.

Original entry on oeis.org

1, 1, 5, 18, 63, 234, 1163, 4953, 24021, 109395, 536457, 2526558, 12324313, 59135699, 288057673, 1396084937, 6800380165, 33152287976, 161670473265, 790996243845, 3863624579433, 18948369852560, 92716137764021, 455475835479225
Offset: 1

Views

Author

R. H. Hardin Feb 17 2013

Keywords

Comments

Column 2 of A222378

Examples

			Some solutions for n=4
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..1....0..1
..0..1....0..0....0..0....1..0....0..0....0..0....0..0....0..0....1..1....2..2
..0..0....0..0....1..0....1..1....0..1....0..0....0..0....0..1....1..1....2..2
..0..0....0..0....1..1....1..1....0..0....1..1....0..1....1..1....1..1....2..2