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%I #5 Aug 12 2016 06:54:16
%S 0,30,138,17658,414138,28493946,1246334388,72638390592,3823498828854,
%T 218021286182580
%N Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one horizontal or vertical neighbor and the top left element equal to 0.
%C Row 4 of A267901.
%e Some solutions for n=4
%e ..0..2..2..2....0..0..3..2....0..0..3..3....0..0..3..3....0..0..0..0
%e ..0..0..3..2....0..0..3..2....0..0..2..3....2..2..1..2....3..3..1..1
%e ..1..0..3..1....1..1..1..2....1..1..2..3....3..3..1..2....3..2..1..1
%e ..1..3..3..1....3..3..1..2....2..2..1..1....0..0..1..1....3..2..2..2
%Y Cf. A267901.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 22 2016
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