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A216025 Number of horizontal, vertical and diagonal neighbor colorings of the odd squares of an nX2 array with new integer colors introduced in row major order.

%I A216025 #6 Jul 22 2025 23:28:50
%S A216025 1,2,2,5,12,42,136,602,2440,12840,61912,373780,2075312,14050312,
%T A216025 87852160,656404264,4548247264,37060650272,281121815712,2475181138384,
%U A216025 20358402201792,192262536609952,1701534399324544,17131843186425504
%N A216025 Number of horizontal, vertical and diagonal neighbor colorings of the odd squares of an nX2 array with new integer colors introduced in row major order.
%C A216025 Column 2 of A216031
%H A216025 R. H. Hardin, <a href="/A216025/b216025.txt">Table of n, a(n) for n = 1..123</a>
%e A216025 Some solutions for n=5
%e A216025 ..x..0....x..0....x..0....x..0....x..0....x..0....x..0....x..0....x..0....x..0
%e A216025 ..1..x....0..x....1..x....0..x....1..x....1..x....0..x....0..x....1..x....1..x
%e A216025 ..x..2....x..1....x..2....x..1....x..2....x..2....x..1....x..1....x..2....x..2
%e A216025 ..0..x....2..x....2..x....2..x....2..x....3..x....1..x....1..x....3..x....3..x
%e A216025 ..x..3....x..0....x..0....x..3....x..3....x..4....x..0....x..2....x..1....x..0
%K A216025 nonn
%O A216025 1,2
%A A216025 _R. H. Hardin_ Aug 30 2012