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A222680 Number of 2Xn 0..3 arrays with no more than floor(2Xn/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..3 order.

%I A222680 #6 Jul 23 2025 02:55:16
%S A222680 2,1,5,10,25,150,359,2249,6511,39991,119033,747758,2254819,14115927,
%T A222680 43486517,268330409,844434635,5129191736,16468845241,98454511005,
%U A222680 322307191185,1896450581728,6325288982445,36644084370361,124416281370753
%N A222680 Number of 2Xn 0..3 arrays with no more than floor(2Xn/2) elements unequal to at least one horizontal, diagonal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
%C A222680 Row 2 of A222679
%H A222680 R. H. Hardin, <a href="/A222680/b222680.txt">Table of n, a(n) for n = 1..45</a>
%e A222680 All solutions for n=3
%e A222680 ..0..1..1....0..0..0....0..0..1....0..0..0....0..0..0
%e A222680 ..1..1..1....0..0..0....0..0..0....0..0..1....1..0..0
%K A222680 nonn
%O A222680 1,1
%A A222680 _R. H. Hardin_ Feb 28 2013