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%I #7 Nov 06 2018 04:12:13
%S 172,484,1376,3904,11020,31104,87888,248568,702724,1985932,5612156,
%T 15862556,44837136,126731180,358188232,1012377900,2861418780,
%U 8087637712,22859103016,64609341900,182613147216,516142417472,1458837964296
%N Number of length n+3 0..4 arrays with no pair in any consecutive four terms totalling exactly 4.
%H R. H. Hardin, <a href="/A246475/b246475.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 2*a(n-1) + a(n-3) + 14*a(n-4) + 3*a(n-5) + 6*a(n-6) + a(n-8) + a(n-9).
%F Empirical g.f.: 4*x*(43 + 35*x + 102*x^2 + 245*x^3 + 80*x^4 + 99*x^5 + 7*x^6 + 21*x^7 + 16*x^8) / (1 - 2*x - x^3 - 14*x^4 - 3*x^5 - 6*x^6 - x^8 - x^9). - _Colin Barker_, Nov 06 2018
%e Some solutions for n=6:
%e ..4....4....0....0....1....2....3....3....3....3....1....3....0....0....4....1
%e ..4....4....0....3....1....0....4....4....2....3....1....0....0....0....2....2
%e ..3....1....0....3....0....3....2....4....0....4....1....3....0....0....3....1
%e ..4....2....1....3....1....3....4....4....0....4....4....0....2....3....4....1
%e ..4....1....1....0....0....0....3....1....3....3....1....3....1....3....4....4
%e ..4....4....2....2....2....0....4....4....0....4....1....0....0....3....4....4
%e ..4....4....4....3....1....0....4....1....2....4....1....0....1....2....4....2
%e ..3....4....1....3....0....3....4....2....0....2....4....2....1....3....4....3
%e ..2....4....4....0....0....3....4....1....3....4....2....3....1....4....4....3
%Y Column 4 of A246479.
%K nonn
%O 1,1
%A _R. H. Hardin_, Aug 27 2014
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