login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A190538
Number of (n+2)X(n+2) symmetric binary matrices without the pattern 0 1 1 diagonally, vertically, antidiagonally or horizontally
1
39, 235, 1473, 12123, 126631, 1757318, 32090135, 788075131, 25821271397, 1137500732205, 67142445815228, 5324910690451856, 566582175357963128, 80968803488105203945, 15531562746293796709197, 4000671284977284767088973
OFFSET
1,1
LINKS
EXAMPLE
Some solutions for 4X4
..1..0..1..0....1..0..0..1....0..0..0..1....1..1..1..1....0..0..1..0
..0..0..0..0....0..0..0..1....0..0..0..0....1..0..0..1....0..0..0..1
..1..0..0..0....0..0..1..0....0..0..0..0....1..0..0..0....1..0..0..0
..0..0..0..0....1..1..0..0....1..0..0..0....1..1..0..1....0..1..0..1
CROSSREFS
Sequence in context: A177709 A211503 A266104 * A190606 A101627 A229639
KEYWORD
nonn
AUTHOR
R. H. Hardin May 12 2011
STATUS
approved