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A221926 Number of nX3 arrays of occupancy after each element stays put or moves to some horizontal, diagonal or antidiagonal neighbor, without move-in move-out straight through or left turns.

%I A221926 #7 Jul 23 2025 02:20:01
%S A221926 6,232,5748,153652,4053833,107220027,2834169558,74925759485,
%T A221926 1980733759947,52362769529788,1384263535086577,36594432454954146,
%U A221926 967411477937300180,25574518045138377146,676088703977133126785
%N A221926 Number of nX3 arrays of occupancy after each element stays put or moves to some horizontal, diagonal or antidiagonal neighbor, without move-in move-out straight through or left turns.
%C A221926 Column 3 of A221929
%H A221926 R. H. Hardin, <a href="/A221926/b221926.txt">Table of n, a(n) for n = 1..41</a>
%e A221926 Some solutions for n=3
%e A221926 ..0..2..0....0..1..1....1..2..0....0..3..0....0..4..1....0..1..1....0..2..1
%e A221926 ..0..1..1....1..3..0....1..2..1....0..2..1....0..1..0....0..5..0....0..2..2
%e A221926 ..2..2..1....2..1..0....1..1..0....0..1..2....1..1..1....2..0..0....0..1..1
%K A221926 nonn
%O A221926 1,1
%A A221926 _R. H. Hardin_ Feb 01 2013