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A248459 Number of length n+2 0..6 arrays with no three consecutive terms having the sum of any two elements equal to twice the third.

%I A248459 #6 Jul 23 2025 11:43:46
%S A248459 282,1652,9684,56782,332940,1952254,11447368,67123652,393591402,
%T A248459 2307892826,13532738130,79351606012,465292191408,2728323147524,
%U A248459 15998005845580,93807139848202,550054773800480,3225343557770222
%N A248459 Number of length n+2 0..6 arrays with no three consecutive terms having the sum of any two elements equal to twice the third.
%C A248459 Column 6 of A248461
%H A248459 R. H. Hardin, <a href="/A248459/b248459.txt">Table of n, a(n) for n = 1..210</a>
%F A248459 Empirical: a(n) = 5*a(n-1) +4*a(n-2) +20*a(n-3) -58*a(n-4) -109*a(n-5) -155*a(n-6) +28*a(n-7) +295*a(n-8) +175*a(n-9) +153*a(n-10) +36*a(n-11) +382*a(n-12) +183*a(n-13) -193*a(n-14) +140*a(n-15) +96*a(n-16)
%e A248459 Some solutions for n=4
%e A248459 ..0....0....3....4....0....5....1....5....1....2....0....6....2....0....4....6
%e A248459 ..4....6....4....0....5....2....5....1....0....1....0....4....0....0....3....3
%e A248459 ..3....0....3....1....4....0....4....0....5....5....3....3....6....6....3....2
%e A248459 ..0....5....6....4....2....5....5....6....4....1....2....1....6....6....2....2
%e A248459 ..5....6....5....1....2....6....2....5....4....1....6....0....4....1....3....1
%e A248459 ..4....5....5....5....3....5....1....0....2....4....0....4....4....5....0....4
%K A248459 nonn
%O A248459 1,1
%A A248459 _R. H. Hardin_, Oct 06 2014