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%I #7 Jul 25 2012 04:55:59
%S 1,3,2,7,19,35,77,176,377,819,1801,3927,8562,18711,40855,89179,194729,
%T 425184,928305,2026855,4425441,9662395,21096706,46062279,100571611,
%U 219586403,479441557,1046805072,2285577449,4990293595,10895727817
%N Number of nX1 0..4 arrays with each element equal to the number its horizontal and vertical neighbors less than or equal to itself
%C Column 1 of A196544
%H R. H. Hardin, <a href="/A196537/b196537.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +3*a(n-3) +a(n-4).
%F Empirical: G.f. x*(x-1)*(x^2+3*x+1) / ( -1+x+x^2+3*x^3+x^4 ). - _R. J. Mathar_, Jul 25 2012
%e All solutions for n=4
%e ..0....0....1....0....0....1....0
%e ..2....1....0....2....2....1....2
%e ..2....2....2....1....1....2....0
%e ..0....0....0....1....0....0....1
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 03 2011
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