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.

A230649 Number of nX5 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j).

Original entry on oeis.org

0, 15, 27, 531, 1635, 28161, 90393, 1539207, 4956927, 84335553, 271665969, 4621740687, 14888070495, 253283346081, 815905965057, 13880597644287, 44713811014239, 760693546670625, 2450435395047009, 41688023124390687
Offset: 1

Views

Author

R. H. Hardin, Oct 27 2013

Keywords

Comments

Column 5 of A230652

Examples

			Some solutions for n=5
..0..x..0..x..0....2..x..2..x..1....1..x..1..x..0....2..x..2..x..0
..x..2..x..2..x....x..0..x..1..x....x..1..x..2..x....x..0..x..2..x
..0..x..1..x..0....2..x..1..x..1....0..x..1..x..0....2..x..2..x..1
..x..0..x..1..x....x..1..x..2..x....x..2..x..0..x....x..0..x..1..x
..2..x..1..x..1....1..x..1..x..0....0..x..0..x..2....2..x..1..x..1
		

Formula

Empirical: a(n) = 59*a(n-2) -230*a(n-4) -2*a(n-6) +32*a(n-8) for n>11