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Number of (n+1)X6 0..1 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements
1

%I #5 Mar 31 2012 12:36:56

%S 972,15564,253068,4136292,67731264,1109832180,18189909480,

%T 298154846436,4887277903812,80111933563464,1313194979326320,

%U 21525927546323460,352853780193705264,5783993041849734792,94811448308361126864

%N Number of (n+1)X6 0..1 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements

%C Column 5 of A203378

%H R. H. Hardin, <a href="/A203375/b203375.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 30*a(n-1) -291*a(n-2) +1278*a(n-3) -2901*a(n-4) +3519*a(n-5) -2152*a(n-6) +516*a(n-7)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Dec 31 2011