login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A232331 Number of nX4 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally, with no adjacent elements equal 1

%I

%S 6,32,154,734,3472,16338,76630,358656,1676330,7828014,36533360,

%T 170436130,794923238,3706958560,17284778298,80589690622,375729468240,

%U 1751693001458,8166429157878,38071572583616,177486683779786,827424427937102

%N Number of nX4 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or antidiagonally, with no adjacent elements equal

%C Column 4 of A232335

%H R. H. Hardin, <a href="/A232331/b232331.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) -9*a(n-2) -8*a(n-3) -4*a(n-4).

%F Empirical: G.f.: -2*x*(-3+5*x+8*x^2+4*x^3) / ( 1-7*x+9*x^2+8*x^3+4*x^4 ). - _R. J. Mathar_, Nov 24 2013

%e Some solutions for n=7

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

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 22 2013

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 28 05:30 EST 2021. Contains 349401 sequences. (Running on oeis4.)