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%I #6 Apr 21 2021 14:38:11
%S 4,10,56,435,4790,50535,547563,5815939,63130202,676152734,7328771224,
%T 79083695286,857913193954,9302185273377,101073333908828,
%U 1099637763169027,11970412457540599,130557727722965457,1423911243991041430
%N Number of n X 4 0..2 arrays with no more than floor(nX4/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..2 order.
%C Column 4 of A222573.
%H R. H. Hardin, <a href="/A222569/b222569.txt">Table of n, a(n) for n = 1..128</a>
%e Some solutions for n=3
%e ..0..0..0..0....0..0..0..0....0..0..0..0....0..1..2..2....0..0..0..1
%e ..0..0..0..0....0..0..0..0....0..0..0..0....2..2..2..2....0..0..0..0
%e ..1..0..2..0....0..0..0..1....0..0..1..0....2..2..2..2....0..0..0..1
%Y Cf. A222573.
%K nonn
%O 1,1
%A _R. H. Hardin_ Feb 25 2013