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%I #5 Dec 01 2014 18:38:49
%S 10,116,2804,157312,18415674,4911447738,2766068478692,
%T 3496332976040148,9445243384724999530,56648036031686971128288,
%U 732454090774743685368594486,20877132584603122578819078333432,1289954839986383433021857780921092718
%N Number of (n+1)X(n+1) 0..1 arrays with every 2X2 subblock having one or two 1s
%C Diagonal of A251326
%H R. H. Hardin, <a href="/A251318/b251318.txt">Table of n, a(n) for n = 1..14</a>
%e Some solutions for n=4
%e ..0..0..1..0..1....0..1..0..1..0....0..1..0..0..1....0..0..0..1..1
%e ..1..0..1..0..0....1..0..1..0..1....1..0..1..0..0....1..1..0..0..0
%e ..1..0..0..1..0....0..1..0..0..0....1..0..1..0..1....0..0..0..1..1
%e ..0..0..1..0..0....0..0..0..1..0....1..0..0..1..0....0..1..0..0..0
%e ..1..1..0..0..1....1..0..1..0..1....0..0..1..0..1....1..0..0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 01 2014
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