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%I #4 Nov 21 2013 06:18:00
%S 215,6189,175431,4987471,141815403,4032714105,114676900023,
%T 3261035421093,92733208328669,2637030152019143,74988542695581639,
%U 2132429753296994177,60639352262137170177,1724385545471376948763,49035904880139271370475
%N Number of (n+1)X(3+1) 0..2 arrays with every element both >= and <= some horizontal or antidiagonal neighbor
%C Column 3 of A232257
%H R. H. Hardin, <a href="/A232252/b232252.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 27*a(n-1) +67*a(n-2) -667*a(n-3) -2143*a(n-4) -874*a(n-5) -67*a(n-6) +187*a(n-7) +95*a(n-8) +16*a(n-9) for n>10
%e Some solutions for n=3
%e ..0..0..0..1....0..0..2..2....0..0..0..1....1..1..1..1....0..0..2..2
%e ..1..1..2..2....2..2..1..1....0..2..2..2....1..1..1..2....0..2..0..0
%e ..2..2..0..1....1..0..2..2....2..2..0..0....0..0..2..1....0..0..2..2
%e ..2..0..1..1....0..1..2..2....1..1..0..0....0..1..0..0....1..1..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 21 2013