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A245999 Number of length 4+2 0..n arrays with no pair in any consecutive three terms totalling exactly n.

%I A245999 #9 Apr 21 2021 15:10:57
%S A245999 2,26,396,2196,9582,29790,80504,185192,391290,753570,1371972,2352636,
%T A245999 3877286,6128486,9405552,13997520,20363634,28934442,40377980,55306340,
%U A245999 74651742,99252846,130367976,169112376,217138922,275894450,347501364
%N A245999 Number of length 4+2 0..n arrays with no pair in any consecutive three terms totalling exactly n.
%C A245999 Row 4 of A245995.
%H A245999 R. H. Hardin, <a href="/A245999/b245999.txt">Table of n, a(n) for n = 1..210</a>
%F A245999 Empirical: a(n) = 3*a(n-1) +a(n-2) -11*a(n-3) +6*a(n-4) +14*a(n-5) -14*a(n-6) -6*a(n-7) +11*a(n-8) -a(n-9) -3*a(n-10) +a(n-11).
%F A245999 Empirical: G.f.: -2*x*(1 +10*x +158*x^2 +502*x^3 +1436*x^4 +1510*x^5 +1498*x^6 +474*x^7 +171*x^8) / ( (1+x)^4*(x-1)^7 ). - _R. J. Mathar_, Aug 10 2014
%e A245999 Some solutions for n=8
%e A245999 ..1....2....1....3....2....0....0....1....1....0....4....0....2....5....5....3
%e A245999 ..4....7....3....2....0....2....2....5....1....7....1....2....2....2....2....7
%e A245999 ..5....5....4....1....7....1....5....5....5....6....6....3....7....1....5....7
%e A245999 ..6....5....1....4....2....8....4....7....8....5....3....4....7....8....7....5
%e A245999 ..8....0....5....0....2....1....8....7....4....4....6....1....4....5....0....2
%e A245999 ..4....1....6....1....7....8....7....4....6....7....1....1....7....5....6....2
%Y A245999 Cf. A245995.
%K A245999 nonn
%O A245999 1,1
%A A245999 _R. H. Hardin_, Aug 09 2014