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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..20

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

Adjacent sequences:  A190535 A190536 A190537 * A190539 A190540 A190541

KEYWORD

nonn

AUTHOR

R. H. Hardin May 12 2011

STATUS

approved

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Last modified December 9 03:23 EST 2021. Contains 349625 sequences. (Running on oeis4.)