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%I #4 Nov 03 2013 07:46:12
%S 3,11,24,89,191,748,1573,6259,13176,52497,110739,441340,931361,
%T 3713195,7836336,31247585,65947255,262980516,555025545,2213339483,
%U 4671332880,18628563209,39316357723,156788159916,330908274229,1319617809715
%N Number of black square subarrays of (n+1)X(4+1) binary arrays with no element equal to a strict majority of its diagonal and antidiagonal neighbors, with upper left element zero
%C Column 4 of A231070
%H R. H. Hardin, <a href="/A231068/b231068.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 14*a(n-2) -61*a(n-4) +148*a(n-6) -289*a(n-8) +325*a(n-10) -227*a(n-12) +95*a(n-14) -28*a(n-16) +4*a(n-18)
%e Some solutions for n=4
%e ..x..0..x..1..x....x..0..x..1..x....x..0..x..0..x....x..0..x..0..x
%e ..1..x..0..x..1....1..x..0..x..0....1..x..1..x..0....0..x..1..x..0
%e ..x..1..x..0..x....x..1..x..1..x....x..0..x..1..x....x..1..x..1..x
%e ..0..x..1..x..1....1..x..0..x..0....0..x..0..x..0....0..x..0..x..1
%e ..x..1..x..0..x....x..0..x..1..x....x..1..x..1..x....x..1..x..0..x
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 03 2013