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Number of (n+2)X7 binary arrays with each 3X3 subblock nonsingular
1

%I #5 Mar 31 2012 12:36:02

%S 52662,886926,14532816,230731304,3749400138,60674682444,978050637454,

%T 15816011545490,255607860729284,4128520011920866,66715825040239470,

%U 1078017197746908576,17417146777474242918,281426703318981682738

%N Number of (n+2)X7 binary arrays with each 3X3 subblock nonsingular

%C Column 5 of A185534

%H R. H. Hardin, <a href="/A185530/b185530.txt">Table of n, a(n) for n = 1..200</a>

%e Some solutions for 4X7

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 30 2011