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!)
A241608 Number of length n+2 0..2 arrays with no consecutive three elements summing to more than 2. 1

%I #9 Oct 30 2018 10:33:49

%S 10,20,40,76,147,287,556,1077,2091,4057,7868,15264,29613,57445,111438,

%T 216184,419380,813563,1578253,3061693,5939450,11522085,22351978,

%U 43361147,84117349,163181309,316559417,614101361,1191310271,2311051970,4483266305

%N Number of length n+2 0..2 arrays with no consecutive three elements summing to more than 2.

%H R. H. Hardin, <a href="/A241608/b241608.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = a(n-1) + a(n-2) + 2*a(n-3) - a(n-5) - a(n-6).

%F Empirical g.f.: x*(10 + 10*x + 10*x^2 - 4*x^3 - 9*x^4 - 6*x^5) / (1 - x - x^2 - 2*x^3 + x^5 + x^6). - _Colin Barker_, Oct 30 2018

%e Some solutions for n=5:

%e ..1....0....2....0....1....2....2....1....0....1....1....0....1....1....1....0

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

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

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

%e ..0....2....0....0....0....1....0....1....1....0....0....0....0....0....1....0

%e ..1....0....1....0....1....0....1....0....0....1....2....0....1....1....1....0

%e ..1....0....0....2....0....0....1....0....0....0....0....2....1....0....0....0

%Y Column 2 of A241619.

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 26 2014

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 March 28 17:25 EDT 2024. Contains 371254 sequences. (Running on oeis4.)