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A260602 Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000101 00010001 or 00010101. 1

%I

%S 40,58,125,241,525,1029,2246,4407,9592,18930,41027,81192,175502,

%T 348438,750714,1494859,3211981,6412772,13742956,27507848,58807987,

%U 117983491,251666242,506004675,1077074116,2169965427,4609962160,9305093538

%N Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000101 00010001 or 00010101.

%H R. H. Hardin, <a href="/A260602/b260602.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + 2*a(n-2) - a(n-3) + 7*a(n-4) - 10*a(n-5) + 6*a(n-6) - 5*a(n-7) - 3*a(n-8) + 6*a(n-9) + 2*a(n-10) - 8*a(n-11) + 4*a(n-12) for n>13.

%F Empirical g.f.: x*(40 + 18*x - 13*x^2 + 40*x^3 - 188*x^4 + 141*x^5 - 127*x^6 + 43*x^7 + 117*x^8 - 70*x^9 - 110*x^10 + 136*x^11 - 36*x^12) / ((1 - x)*(1 - 2*x^2 - x^3 - 8*x^4 + 2*x^5 - 4*x^6 + x^7 + 4*x^8 - 2*x^9 - 4*x^10 + 4*x^11)). - _Colin Barker_, Dec 29 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 1 of A260609.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 29 2015

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Last modified October 19 17:24 EDT 2021. Contains 348091 sequences. (Running on oeis4.)