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 A185481 Number of (n+1)X4 binary arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant 1

%I

%S 76,684,4740,35672,260172,1923780,14150114,104300522,768160718,

%T 5659345888,41689048326,307115065572,2262407666898,16666499139956,

%U 122776828884698,904459332925242,6662871472736956,49083319176509768

%N Number of (n+1)X4 binary arrays with every 2X2 subblock determinant equal to some horizontal or vertical neighbor 2X2 subblock determinant

%C Column 3 of A185487

%H R. H. Hardin, <a href="/A185481/b185481.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=11*a(n-1)-23*a(n-2)-69*a(n-3)+409*a(n-4)-768*a(n-5)-571*a(n-6)+4622*a(n-7)-5573*a(n-8)+1199*a(n-9)+2111*a(n-10)-8400*a(n-11)+12500*a(n-12)-4419*a(n-13)-490*a(n-14)+204*a(n-15)-1290*a(n-16)+1264*a(n-17)-1204*a(n-18)+320*a(n-19) for n>22

%e Some solutions for 3X4

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 28 2011

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)