login
A181272
Number of 4 X n binary matrices M with rows in strictly increasing order and rows of M*transpose(M) (mod 2) in strictly increasing order.
1
0, 0, 4, 111, 1793, 32124, 513260, 8397376, 133979600, 2151884352, 34376925632, 550298217984, 8799317537024, 140789221362688, 2252143151246336, 36033204166164480, 576491512426680320, 9223724397701578752
OFFSET
1,3
LINKS
EXAMPLE
M and M*transpose(M) (mod 2) for 4 X 3:
..0..0..0......0..0..0..0
..0..1..1......0..0..0..1
..1..0..0......0..0..1..1
..1..1..0......0..1..1..0
CROSSREFS
Row 4 of A181266.
Sequence in context: A286424 A358806 A358779 * A214107 A202518 A212655
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 10 2010
STATUS
approved