A204101 Number of (n+1)X(n+1) 0..2 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) such that b(i,j)*b(i-1,j)-c(i,j)*c(i,j-1) is nonzero.

36, 864, 46656, 5738688, 1631513664, 1084257353088, 1688734588654656, 6186063092597707968, 53367767165496952526400, 1085885663438501136777646080, 52151788282239671615810458238016

Offset: 1

Author

R. H. Hardin Jan 10 2012

Keywords

• nonn

Comments

Also 0..2 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements

Diagonal of A204106

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..13