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A222874 Number of nX4 0..3 arrays with no more than floor(nX4/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

%I A222874 #6 Jul 23 2025 03:11:30
%S A222874 11,1814,409775,95867967,22794825314,5472896849943,1322676376672081,
%T A222874 321195816580955511,78284744747263499257,19135706630178881122106,
%U A222874 4688528991184907785652449,1151011442556048521433434944
%N A222874 Number of nX4 0..3 arrays with no more than floor(nX4/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
%C A222874 Column 4 of A222878
%H A222874 R. H. Hardin, <a href="/A222874/b222874.txt">Table of n, a(n) for n = 1..97</a>
%e A222874 Some solutions for n=3
%e A222874 ..0..1..0..2....0..1..0..1....0..0..1..2....0..0..0..1....0..0..1..2
%e A222874 ..0..3..1..1....0..1..2..0....1..3..1..0....2..1..1..2....1..3..1..3
%e A222874 ..2..0..2..2....1..1..2..2....1..1..3..2....0..3..0..2....3..3..1..2
%K A222874 nonn
%O A222874 1,1
%A A222874 _R. H. Hardin_ Mar 08 2013