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A245994 Number of length n+2 0..7 arrays with no pair in any consecutive three terms totalling exactly 7.

%I A245994 #8 Jun 02 2025 10:13:44
%S A245994 344,2120,13064,80504,496088,3057032,18838280,116086712,715358552,
%T A245994 4408238024,27164786696,167396958200,1031546535896,6356676173576,
%U A245994 39171603577352,241386297637688,1487489389403480,9166322634058568
%N A245994 Number of length n+2 0..7 arrays with no pair in any consecutive three terms totalling exactly 7.
%C A245994 Column 7 of A245995
%H A245994 R. H. Hardin, <a href="/A245994/b245994.txt">Table of n, a(n) for n = 1..210</a>
%F A245994 Empirical: a(n) = 6*a(n-1) +a(n-2).
%F A245994 Empirical: G.f.: -8*x*(43+7*x) / ( -1+6*x+x^2 ). - _R. J. Mathar_, Aug 10 2014
%e A245994 Some solutions for n=4
%e A245994 ..5....1....5....1....7....6....7....7....0....4....2....7....0....1....7....6
%e A245994 ..6....0....3....3....6....6....4....1....6....1....6....5....2....3....6....5
%e A245994 ..3....0....3....3....5....2....6....7....2....5....0....5....0....7....2....4
%e A245994 ..7....4....5....3....4....2....4....5....4....3....6....1....1....7....7....1
%e A245994 ..3....6....3....2....7....2....6....1....1....5....6....0....5....6....7....2
%e A245994 ..7....5....6....3....1....7....6....3....0....6....6....0....7....5....7....2
%K A245994 nonn
%O A245994 1,1
%A A245994 _R. H. Hardin_, Aug 09 2014