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%I #5 Mar 31 2012 12:35:53
%S 50,4594,2235330,5848268518,81648038954018,6101430466182955346,
%T 2437545227670570289677842,5208444026905229671830632661366,
%U 59514652522597099528978017843617001686
%N Number of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock nonsingular
%C Diagonal of A183698
%e Some solutions for 3X3
%e ..2..0..2....2..1..0....2..0..1....2..2..1....2..1..0....2..2..1....2..0..1
%e ..1..2..2....1..0..2....1..2..2....0..1..2....2..2..2....0..1..1....0..1..1
%e ..1..1..0....0..2..1....2..2..0....2..2..2....2..1..0....2..2..1....2..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 06 2011