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Number of nX3 binary arrays without the pattern 0 1 0 diagonally, vertically or horizontally
1

%I #5 Mar 31 2012 12:36:12

%S 7,49,229,971,4351,20124,92597,423074,1932355,8836938,40424590,

%T 184890099,845559045,3867059514,17685848557,80885615913,369926354240,

%U 1691838530486,7737537171921,35387239493020,161841764228828,740175150497968

%N Number of nX3 binary arrays without the pattern 0 1 0 diagonally, vertically or horizontally

%C Column 3 of A188508

%H R. H. Hardin, <a href="/A188502/b188502.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=7*a(n-1)-21*a(n-2)+59*a(n-3)-82*a(n-4)+97*a(n-5)-14*a(n-6)-148*a(n-7)+166*a(n-8)-153*a(n-9)-158*a(n-10)+340*a(n-11)+164*a(n-12)-296*a(n-13)-87*a(n-14)+115*a(n-15)+13*a(n-16)-a(n-17)+6*a(n-18)-5*a(n-19)-6*a(n-20)+4*a(n-21)+a(n-23)

%e Some solutions for 4X3

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 02 2011