cp's OEIS Frontend

A249284 Number of length n+3 0..2 arrays with no four consecutive terms having the sum of any three elements equal to three times the fourth.

%I A249284 #7 Jul 23 2025 11:57:45
%S A249284 66,168,428,1094,2792,7132,18232,46616,119176,304696,779066,1992002,
%T A249284 5093330,13023126,33299000,85142802,217703012,556648464,1423304428,
%U A249284 3639273226,9305324178,23792953554,60836640416,155554327024,397739724496
%N A249284 Number of length n+3 0..2 arrays with no four consecutive terms having the sum of any three elements equal to three times the fourth.
%C A249284 Column 2 of A249290
%H A249284 R. H. Hardin, <a href="/A249284/b249284.txt">Table of n, a(n) for n = 1..210</a>
%F A249284 Empirical: a(n) = a(n-1) +2*a(n-2) +3*a(n-3) +7*a(n-4) +a(n-5) -6*a(n-6) -12*a(n-7) -14*a(n-8) -14*a(n-9) -7*a(n-10) +3*a(n-11) +2*a(n-12)
%e A249284 Some solutions for n=9
%e A249284 ..1....0....2....2....1....1....0....1....1....1....0....1....1....2....2....1
%e A249284 ..1....0....1....0....0....1....1....0....1....0....0....1....1....0....1....0
%e A249284 ..0....1....0....0....2....0....2....2....2....2....0....1....2....0....0....2
%e A249284 ..1....0....0....0....2....1....0....2....2....0....2....2....1....0....0....2
%e A249284 ..0....1....2....1....0....0....0....0....1....2....2....2....2....1....1....2
%e A249284 ..2....0....2....0....0....0....0....1....2....1....0....0....2....0....1....0
%e A249284 ..0....1....2....0....0....1....2....0....2....2....2....2....1....0....0....0
%e A249284 ..2....1....0....1....1....1....0....1....2....1....0....2....0....1....0....2
%e A249284 ..0....0....0....1....2....0....2....0....0....2....2....1....0....0....2....2
%e A249284 ..2....0....2....1....2....1....1....0....0....1....1....2....0....2....1....2
%e A249284 ..2....0....2....2....1....0....2....0....1....2....2....0....2....0....2....1
%e A249284 ..2....2....1....2....2....0....2....1....2....0....1....0....2....0....2....0
%K A249284 nonn
%O A249284 1,1
%A A249284 _R. H. Hardin_, Oct 24 2014