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%I #13 Jul 09 2018 17:34:49
%S 32,80,156,512,1076,4004,8612,33716,73028,291908,633732,2555588,
%T 5552900,22478852,48859652,198127364,430707716,1747864580,3799906308,
%U 15425772548,33536978948,136164892676,296038014980,1202040352772,2613387280388
%N 1/4 the number of (n+1) X 5 0..2 arrays with every 2 X 2 subblock having distinct edge sums.
%C Column 4 of A209382.
%H R. H. Hardin, <a href="/A209378/b209378.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 3*a(n-1) + 12*a(n-2) - 42*a(n-3) - 24*a(n-4) + 156*a(n-5) - 48*a(n-6) - 168*a(n-7) + 112*a(n-8).
%F Empirical g.f.: 4*x*(8 - 4*x - 117*x^2 + 107*x^3 + 449*x^4 - 472*x^5 - 502*x^6 + 548*x^7) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)*(1 - 12*x^2 + 28*x^4)). - _Colin Barker_, Jul 09 2018
%e Some solutions for n=4:
%e ..0..2..2..2..0....2..0..2..0..2....1..2..2..2..1....0..0..2..1..2
%e ..0..1..0..1..0....1..0..1..0..1....0..0..1..0..0....2..1..2..0..2
%e ..2..2..2..2..2....2..2..2..0..2....1..2..2..2..1....2..0..2..1..2
%e ..0..1..0..1..0....1..0..1..0..1....0..0..1..0..0....2..1..2..0..2
%e ..0..2..0..2..2....2..0..2..2..2....1..2..2..2..1....0..0..2..1..2
%Y Cf. A209382.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 07 2012
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