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

 

Logo

Invitation: celebrating 50 years of OEIS, 250000 sequences, and Sloane's 75th, there will be a conference at DIMACS, Rutgers, Oct 9-10 2014.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A209651 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically 2
8, 64, 216, 630, 2156, 7128, 24990, 87136, 311040, 1112150, 4018716, 14563584, 53065350, 193861408, 710502760, 2609417910, 9603620076, 35401092264, 130688898510, 483039609408, 1787282764624, 6619084515926, 24532925650268 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A209650

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 9*a(n-1) -11*a(n-2) -108*a(n-3) +272*a(n-4) +480*a(n-5) -1754*a(n-6) -942*a(n-7) +5482*a(n-8) +552*a(n-9) -9304*a(n-10) +888*a(n-11) +8539*a(n-12) -1755*a(n-13) -3871*a(n-14) +1092*a(n-15) +648*a(n-16) -216*a(n-17) for n>18

EXAMPLE

Some solutions for n=4

..1..1..1..1....1..0..1..0....1..0..1..0....1..1..0..1....1..0..1..1

..1..1..1..1....1..0..1..0....0..0..0..0....0..0..0..0....1..1..0..1

..1..1..1..1....1..0..1..0....0..0..0..0....0..0..0..0....0..1..0..1

..1..1..1..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0

CROSSREFS

Sequence in context: A207940 A016743 A086114 * A207071 A117219 A207404

Adjacent sequences:  A209648 A209649 A209650 * A209652 A209653 A209654

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 11 2012

STATUS

approved

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

Content is available under The OEIS End-User License Agreement .

Last modified July 28 16:32 EDT 2014. Contains 245003 sequences.