A272960 - OEIS

%I #4 May 11 2016 15:01:25

%S 1,1,0,1,9,6,16,66,95,177,493,1153,2238,5011,11642,25096,55321,123997,

%T 273017,600569,1336351,2963793,6536040,14463667,32057919,70930270,

%U 156916549,347367018,768795181,1701248904,3765540655,8334284668

%N Number of nX3 0..1 arrays with exactly n+3-1 having value 1 and no three 1s forming an isosceles right triangle.

%C Column 3 of A272965.

%H R. H. Hardin, <a href="/A272960/b272960.txt">Table of n, a(n) for n = 1..210</a>

%F 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)

%e All solutions for n=6

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

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

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

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

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

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

%Y Cf. A272965.

%K nonn

%O 1,5

%A _R. H. Hardin_, May 11 2016