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Number of nX4 0..1 arrays with exactly n+4-1 having value 1 and no three 1s forming an isosceles right triangle.
1

%I #4 May 11 2016 15:02:07

%S 1,0,1,0,8,8,71,212,731,1840,5953,18632,54705,171348,511899,1608540,

%T 4861373,14726040,45536993,138776184,426552305,1305642816,3998654049,

%U 12283464960,37639150053,115651510068,355188064346,1090663423924

%N Number of nX4 0..1 arrays with exactly n+4-1 having value 1 and no three 1s forming an isosceles right triangle.

%C Column 4 of A272965.

%H R. H. Hardin, <a href="/A272961/b272961.txt">Table of n, a(n) for n = 1..113</a>

%e Some solutions for n=6

%e ..1..1..0..1. .1..1..1..0. .0..1..1..1. .1..0..1..1. .1..0..1..1

%e ..0..0..0..1. .0..0..0..0. .0..0..0..0. .1..0..0..0. .1..0..0..0

%e ..0..0..1..0. .0..1..0..0. .0..0..1..0. .0..1..0..0. .0..1..0..0

%e ..0..0..0..0. .0..0..1..0. .0..1..0..0. .0..0..0..0. .0..0..1..0

%e ..0..0..0..0. .0..0..0..1. .1..0..0..0. .0..0..0..0. .0..0..0..0

%e ..1..1..1..1. .1..1..0..1. .1..0..1..1. .1..1..1..1. .0..1..1..1

%Y Cf. A272965.

%K nonn

%O 1,5

%A _R. H. Hardin_, May 11 2016