A203445 - OEIS

A203445

Number of (n+1)X(n+1) 0..1 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 rows of b(i,j) and columns of c(i,j) are lexicographically nondecreasing

%I #5 Mar 31 2012 12:36:56

%S 8,34,321,7481,554620,125140148,91479447926,216607480473481,

%T 1675743278510590472,42706348945332757503203

%N Number of (n+1)X(n+1) 0..1 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 rows of b(i,j) and columns of c(i,j) are lexicographically nondecreasing

%C Diagonal of A203452

%e Some solutions for n=4

%e ..0..0..0..1..1....0..0..0..1..1....0..0..1..1..1....0..0..0..0..0

%e ..0..0..1..1..1....0..0..0..1..1....0..0..1..1..1....0..0..0..1..1

%e ..0..1..0..0..0....0..0..1..0..1....0..1..0..1..1....0..1..1..1..1

%e ..1..0..1..1..1....0..1..0..1..1....0..1..1..1..1....1..1..1..0..0

%e ..0..1..1..1..1....1..1..1..0..0....1..1..0..0..1....1..1..1..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 02 2012