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A272960
Number of nX3 0..1 arrays with exactly n+3-1 having value 1 and no three 1s forming an isosceles right triangle.
1
1, 1, 0, 1, 9, 6, 16, 66, 95, 177, 493, 1153, 2238, 5011, 11642, 25096, 55321, 123997, 273017, 600569, 1336351, 2963793, 6536040, 14463667, 32057919, 70930270, 156916549, 347367018, 768795181, 1701248904, 3765540655, 8334284668
OFFSET
1,5
COMMENTS
Column 3 of A272965.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) -3*a(n-2) +4*a(n-3) -6*a(n-5) +3*a(n-6) -6*a(n-7) -16*a(n-8) +44*a(n-9) -14*a(n-10) -42*a(n-11) +65*a(n-12) -56*a(n-13) +52*a(n-14) -8*a(n-15) -65*a(n-16) +63*a(n-17) -43*a(n-18) +64*a(n-19) -6*a(n-20) -119*a(n-21) +122*a(n-22) +42*a(n-23) -93*a(n-24) +16*a(n-25) +20*a(n-26) -6*a(n-27) -8*a(n-28) -2*a(n-30) -2*a(n-31) +4*a(n-32)
EXAMPLE
All solutions for n=6
..1..1..0. .0..1..1. .1..1..0. .1..0..1. .1..1..1. .0..1..1
..0..0..1. .1..0..0. .0..0..1. .1..0..1. .0..0..0. .1..0..0
..1..0..0. .0..0..1. .0..0..1. .0..0..0. .0..1..0. .1..0..0
..1..0..0. .0..0..1. .0..0..1. .0..0..0. .0..1..0. .1..0..0
..0..0..1. .1..0..0. .0..0..1. .1..0..1. .0..0..0. .1..0..0
..1..1..0. .0..1..1. .1..1..0. .1..0..1. .1..1..1. .0..1..1
CROSSREFS
Cf. A272965.
Sequence in context: A180856 A166520 A102648 * A040074 A088999 A073782
KEYWORD
nonn
AUTHOR
R. H. Hardin, May 11 2016
STATUS
approved