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A260278 Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011. 1

%I #8 Dec 28 2018 15:35:06

%S 46,85,230,525,1150,2726,6351,14393,33241,77098,177043,407486,941020,

%T 2167955,4992417,11510489,26530166,61125209,140873214,324678646,

%U 748199483,1724247325,3973747017,9157675382,21104202919,48636225966

%N Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00001011.

%H R. H. Hardin, <a href="/A260278/b260278.txt">Table of n, a(n) for n = 1..210</a>

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

%F Empirical g.f.: x*(46 + 39*x + 145*x^2 - 27*x^3 - 16*x^4 - 165*x^5 - 43*x^6 + 16*x^7 + 41*x^8 - 19*x^9 + 12*x^10 + 4*x^11) / ((1 + x^2 - x^3)*(1 - x - x^2 - 5*x^3 - x^4 + 3*x^5 + 3*x^6)). - _Colin Barker_, Dec 28 2018

%e Some solutions for n=4:

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

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

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

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

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

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

%Y Column 2 of A260284.

%K nonn

%O 1,1

%A _R. H. Hardin_, Jul 22 2015

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Last modified April 24 10:53 EDT 2024. Contains 371936 sequences. (Running on oeis4.)