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A228735 Number of arrays of the median of three adjacent elements of some length -(n+2) 0..3 array.

%I A228735 #13 Sep 02 2013 13:02:51
%S A228735 4,16,64,232,696,2072,6130,18378,55716,169734,517764,1578184,4806344,
%T A228735 14629384,44519552,135480532,412314438,1254882280,3819338704,
%U A228735 11624541548,35380360780,107682931160,327740673246,997501106370,3035962621026
%N A228735 Number of arrays of the median of three adjacent elements of some length -(n+2) 0..3 array.
%H A228735 R. H. Hardin, <a href="/A228735/b228735.txt">Table of n, a(n) for n = 1..210</a>
%F A228735 Empirical: a(n) = 4*a(n-1) -2*a(n-2) -6*a(n-3) +6*a(n-4) +15*a(n-5) -11*a(n-6) +a(n-7) +a(n-8) +3*a(n-9) +24*a(n-10) -3*a(n-11) -35*a(n-12) -28*a(n-13) +22*a(n-14) +18*a(n-15) -9*a(n-16) -11*a(n-17) -4*a(n-18) +15*a(n-19) +15*a(n-20) -2*a(n-21) -4*a(n-22) -4*a(n-23) -3*a(n-24) +a(n-25) +a(n-26)
%e A228735 Some solutions for n=4
%e A228735 ..2..2..3..3..1..1..2..1..2..3..0..3..0..2..0..1
%e A228735 ..0..3..2..1..1..0..2..1..3..2..0..2..1..0..1..0
%e A228735 ..2..3..1..2..0..1..0..2..3..0..1..0..3..2..0..2
%e A228735 ..1..3..1..1..2..1..0..0..1..2..0..0..3..3..3..1
%Y A228735 Column 3 of A228740.
%K A228735 nonn
%O A228735 1,1
%A A228735 _R. H. Hardin_ Sep 01 2013