The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A255990 Number of length n+6 0..1 arrays with at most one downstep in every 6 consecutive neighbor pairs. 1

%I #7 Jan 24 2018 14:52:15

%S 64,98,156,257,428,705,1134,1797,2848,4560,7384,12021,19508,31444,

%T 50432,80828,129904,209549,338650,546939,881612,1418697,2281990,

%U 3673412,5919888,9546459,15393334,24807246,39956320,64344494,103638460,166985169

%N Number of length n+6 0..1 arrays with at most one downstep in every 6 consecutive neighbor pairs.

%C Column 6 of A255992.

%H R. H. Hardin, <a href="/A255990/b255990.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) -a(n-2) +5*a(n-6) -4*a(n-7).

%F Empirical g.f.: x*(64 - 30*x + 24*x^2 + 43*x^3 + 70*x^4 + 106*x^5 - 168*x^6) / (1 - 2*x + x^2 - 5*x^6 + 4*x^7). - _Colin Barker_, Jan 24 2018

%e Some solutions for n=4:

%e ..0....0....0....0....0....0....0....0....0....1....0....0....0....0....0....0

%e ..0....1....0....0....0....0....1....1....1....1....0....0....0....1....0....1

%e ..0....0....0....0....0....0....1....0....0....1....0....0....1....0....0....0

%e ..0....0....0....0....0....0....0....0....0....1....0....0....0....0....0....1

%e ..0....0....1....1....0....1....0....0....1....1....0....1....0....0....0....1

%e ..0....0....1....0....1....0....0....0....1....1....0....0....0....0....0....1

%e ..0....1....1....0....1....0....0....1....1....0....0....1....0....0....1....1

%e ..0....1....1....0....1....0....0....1....1....0....1....1....0....1....0....1

%e ..0....0....1....1....1....0....0....0....0....0....1....1....0....1....0....1

%e ..0....1....0....1....1....0....0....0....1....0....0....1....0....1....1....0

%Y Cf. A255992.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 13 2015

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 19 20:42 EDT 2024. Contains 372703 sequences. (Running on oeis4.)