cp's OEIS Frontend

A256814 Number of length n+6 0..1 arrays with at most two downsteps in every 6 consecutive neighbor pairs.

%I A256814 #7 Jan 24 2018 09:30:02
%S A256814 120,229,442,856,1656,3204,6192,11955,23088,44617,86226,166620,321960,
%T A256814 622104,1202016,2322567,4487848,8671757,16756074,32377024,62560664,
%U A256814 120883084,233577104,451331323,872088416,1685098737,3256043394
%N A256814 Number of length n+6 0..1 arrays with at most two downsteps in every 6 consecutive neighbor pairs.
%C A256814 Column 6 of A256816.
%H A256814 R. H. Hardin, <a href="/A256814/b256814.txt">Table of n, a(n) for n = 1..210</a>
%F A256814 Empirical: a(n) = 2*a(n-1) -a(n-2) +2*a(n-3) -a(n-4) +3*a(n-6) -2*a(n-7) -6*a(n-9) +4*a(n-10).
%F A256814 Empirical g.f.: x*(120 - 11*x + 104*x^2 - 39*x^3 + 48*x^4 + 93*x^5 - 190*x^6 - 128*x^7 - 250*x^8 + 252*x^9) / ((1 - x)*(1 - x - 2*x^3 - x^4 - x^5 - 4*x^6 - 2*x^7 - 2*x^8 + 4*x^9)). - _Colin Barker_, Jan 24 2018
%e A256814 Some solutions for n=4:
%e A256814 ..1....1....0....0....1....1....1....0....1....0....1....1....0....0....0....0
%e A256814 ..1....0....1....0....0....1....0....1....0....0....0....0....0....1....0....0
%e A256814 ..1....0....0....1....0....1....0....1....1....0....0....0....0....0....1....1
%e A256814 ..0....0....1....1....1....1....0....0....1....1....0....1....1....0....1....0
%e A256814 ..1....0....1....1....0....0....0....0....0....0....1....0....1....0....0....1
%e A256814 ..1....1....1....1....1....1....0....0....1....0....0....0....0....0....1....0
%e A256814 ..1....0....1....0....1....1....0....1....1....0....0....1....0....1....0....0
%e A256814 ..1....1....0....1....0....1....0....0....1....1....1....1....1....0....0....0
%e A256814 ..0....0....0....0....0....0....0....1....0....0....0....1....1....0....1....1
%e A256814 ..1....0....1....1....0....0....0....0....1....0....0....1....1....1....1....0
%Y A256814 Cf. A256816.
%K A256814 nonn
%O A256814 1,1
%A A256814 _R. H. Hardin_, Apr 10 2015