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%I #6 Sep 23 2014 16:34:02
%S 8,90,456,1592,4344,10098,20816,39264,69000,114650,181848,277560,
%T 409976,588882,825504,1132928,1525896,2021274,2637800,3396600,4320888,
%U 5436530,6771696,8357472,10227464,12418458,14969976,17924984,21329400,25232850
%N Number of length 2+3 0..n arrays with no disjoint pairs in any consecutive four terms having the same sum
%C Row 2 of A247726
%H R. H. Hardin, <a href="/A247728/b247728.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) -4*a(n-2) -4*a(n-3) +10*a(n-4) -4*a(n-5) -4*a(n-6) +4*a(n-7) -a(n-8)
%F Empirical for n mod 2 = 0: a(n) = 1*n^5 + 1*n^4 + (9/2)*n^3 + (3/2)*n^2
%F Empirical for n mod 2 = 1: a(n) = 1*n^5 + 1*n^4 + (9/2)*n^3 + (3/2)*n^2 - (3/2)*n + (3/2).
%F Empirical G.f.: 2*x*(4+29*x+64*x^2+80*x^3+40*x^4+23*x^5) / ( (1+x)^2*(x-1)^6 ). - _R. J. Mathar_, Sep 23 2014
%e Some solutions for n=6
%e ..6....5....2....0....1....3....1....1....6....3....6....3....0....6....6....4
%e ..3....3....3....4....3....4....2....0....6....6....5....3....5....4....4....2
%e ..2....3....0....0....1....1....2....6....6....1....0....2....1....0....0....6
%e ..4....6....3....0....0....1....5....4....5....1....2....6....3....0....0....3
%e ..2....5....3....1....0....3....2....0....2....2....0....6....4....1....5....4
%K nonn
%O 1,1
%A _R. H. Hardin_, Sep 23 2014
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