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!)
A228664 Number of 5 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally. 1

%I #12 Sep 12 2018 09:07:47

%S 16,29,574,2228,24109,128740,1096624,6780585,51990406,344168764,

%T 2516149353,17192729316,122982062328,852741876277,6038989672654,

%U 42158071124804,297183800090933,2081125389730084,14639300678885312

%N Number of 5 X n binary arrays with top left value 1 and no two ones adjacent horizontally, diagonally or antidiagonally.

%H R. H. Hardin, <a href="/A228664/b228664.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) + 34*a(n-2) - 76*a(n-3) - 134*a(n-4) + 258*a(n-5) + 45*a(n-6) - 102*a(n-7).

%F Empirical g.f.: x*(16 - 35*x - 86*x^2 + 162*x^3 + 29*x^4 - 66*x^5) / (1 - 4*x - 34*x^2 + 76*x^3 + 134*x^4 - 258*x^5 - 45*x^6 + 102*x^7). - _Colin Barker_, Sep 12 2018

%e Some solutions for n=4:

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

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

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

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

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

%Y Row 5 of A228660.

%K nonn

%O 1,1

%A _R. H. Hardin_, Aug 29 2013

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 April 23 02:53 EDT 2024. Contains 371906 sequences. (Running on oeis4.)