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%I #4 Nov 17 2013 07:46:35
%S 8,21,80,318,1315,5364,21680,87452,352931,1425261,5757064,23253889,
%T 93921193,379334811,1532086339,6187939435,24992490166,100942222266,
%U 407695589939,1646641727295,6650621491464,26861196902537,108489696252447
%N Number of 3Xn 0..1 arrays with no element less than a strict majority of its horizontal and antidiagonal neighbors
%C Row 3 of A232047
%H R. H. Hardin, <a href="/A232049/b232049.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 8*a(n-1) -27*a(n-2) +64*a(n-3) -104*a(n-4) +124*a(n-5) -102*a(n-6) +34*a(n-7) +10*a(n-8) -34*a(n-9) +19*a(n-10) -2*a(n-11) +a(n-12) +10*a(n-13) -2*a(n-14) -2*a(n-15) for n>18
%e Some solutions for n=7
%e ..0..0..0..0..0..0..0....0..0..0..1..1..1..1....1..0..0..0..0..0..1
%e ..1..0..0..1..0..0..1....1..0..0..0..1..0..0....0..0..0..0..0..1..0
%e ..1..1..1..0..0..1..1....1..1..0..0..0..0..1....0..0..1..1..1..0..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 17 2013