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A272961
Number of nX4 0..1 arrays with exactly n+4-1 having value 1 and no three 1s forming an isosceles right triangle.
1
1, 0, 1, 0, 8, 8, 71, 212, 731, 1840, 5953, 18632, 54705, 171348, 511899, 1608540, 4861373, 14726040, 45536993, 138776184, 426552305, 1305642816, 3998654049, 12283464960, 37639150053, 115651510068, 355188064346, 1090663423924
OFFSET
1,5
COMMENTS
Column 4 of A272965.
LINKS
EXAMPLE
Some solutions for n=6
..1..1..0..1. .1..1..1..0. .0..1..1..1. .1..0..1..1. .1..0..1..1
..0..0..0..1. .0..0..0..0. .0..0..0..0. .1..0..0..0. .1..0..0..0
..0..0..1..0. .0..1..0..0. .0..0..1..0. .0..1..0..0. .0..1..0..0
..0..0..0..0. .0..0..1..0. .0..1..0..0. .0..0..0..0. .0..0..1..0
..0..0..0..0. .0..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0
..1..1..1..1. .1..1..0..1. .1..0..1..1. .1..1..1..1. .0..1..1..1
CROSSREFS
Cf. A272965.
Sequence in context: A183395 A019216 A020552 * A117861 A186984 A298962
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 11 2016
STATUS
approved