login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A186879 Number of (n+2)X9 0..3 arrays with every 3X3 subblock commuting with each horizontal and vertical neighbor 3X3 subblock 1
277659, 21661, 37576, 121144, 260584, 338176, 443560, 571984, 798832, 1272712, 2086288, 3350152, 5585728, 9225664, 15403771, 25918654, 43087345, 71662141, 119953993, 199127077, 331052797, 553674334, 920445640, 1531199242, 2558915851 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A186881

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=2*a(n-1)-a(n-2)+3*a(n-3)-6*a(n-4)+3*a(n-5)+3*a(n-6)-3*a(n-7) for n>15

EXAMPLE

Some solutions for 4X9

..1..0..0..0..0..0..0..2..3....0..0..0..0..0..0..0..1..3

..0..0..0..0..0..0..0..0..0....3..0..0..0..0..0..0..0..1

..0..0..0..0..0..0..0..0..0....0..3..0..0..0..0..0..0..0

..0..1..0..0..0..0..0..0..0....2..0..3..0..0..0..0..0..0

CROSSREFS

Sequence in context: A271349 A295472 A162765 * A224252 A236017 A252209

Adjacent sequences:  A186876 A186877 A186878 * A186880 A186881 A186882

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 28 2011

STATUS

approved

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 October 23 16:46 EDT 2019. Contains 328373 sequences. (Running on oeis4.)