A184595 1/4 the number of (n+1) X (n+1) binary arrays with equal numbers of 2 X 2 subblocks with sums 1 and 3.

2, 24, 1986, 782948, 1291076970, 8783684627835, 245608218357699105, 28056029360014523631654, 13030390694954764597618159782

Offset

1,1

Comments

Diagonal of A184604.

Links

Table of n, a(n) for n=1..9.

Example

Some solutions for 3 X 3:
..1..0..0....0..0..1....0..1..1....1..1..1....1..0..0....1..0..0....1..1..1
..1..1..0....1..1..0....1..0..0....1..0..0....1..0..1....1..0..1....0..0..0
..1..0..0....1..1..0....0..1..1....0..1..0....1..1..0....0..1..1....1..1..1

Crossrefs

Sequence in context: A280922 A296589 A053995 * A369678 A262206 A240993

Adjacent sequences: A184592 A184593 A184594 * A184596 A184597 A184598

Keyword

nonn

Author

R. H. Hardin, Jan 18 2011

Status

approved