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A272967
Number of nX2 0..1 arrays with exactly n+2-2 having value 1 and no three 1s forming an isosceles triangle.
0
2, 6, 10, 21, 14, 28, 18, 29, 22, 32, 26, 36, 30, 40, 34, 44, 38, 48, 42, 52, 46, 56, 50, 60, 54, 64, 58, 68, 62, 72
OFFSET
1,1
COMMENTS
Column 2 of A272973.
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) -a(n-3) for n>11
EXAMPLE
All solutions for n=3
..1..0. .1..1. .1..0. .1..0. .0..1. .1..0. .0..1. .1..1. .0..1. .0..1
..0..0. .0..0. .1..0. .1..0. .0..1. .0..1. .0..1. .0..0. .1..0. .0..0
..1..1. .1..0. .0..1. .1..0. .0..1. .0..1. .1..0. .0..1. .1..0. .1..1
CROSSREFS
Cf. A272973.
Sequence in context: A009325 A308346 A192390 * A067716 A125518 A083176
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 11 2016
STATUS
approved