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A222879 Number of 2Xn 0..3 arrays with no more than floor(2Xn/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

%I A222879 #6 Jul 23 2025 03:12:06
%S A222879 2,11,122,1814,26311,399849,6013669,91842381,1400573929,21492587457,
%T A222879 330100781811,5085688832352,78450837933529,1212393597214424,
%U A222879 18758126651572197,290589347000277975,4505965014075887115
%N A222879 Number of 2Xn 0..3 arrays with no more than floor(2Xn/2) elements equal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
%C A222879 Row 2 of A222878
%H A222879 R. H. Hardin, <a href="/A222879/b222879.txt">Table of n, a(n) for n = 1..60</a>
%e A222879 Some solutions for n=3
%e A222879 ..0..0..1....0..1..2....0..1..2....0..1..1....0..1..2....0..0..1....0..1..2
%e A222879 ..0..2..3....2..1..3....1..0..2....0..1..0....3..0..1....2..3..2....2..2..3
%K A222879 nonn
%O A222879 1,1
%A A222879 _R. H. Hardin_ Mar 08 2013