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

 

Logo

The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A209101 Number of 2Xn 0..2 arrays with new values 0..2 introduced in row major order and no element equal to more than one of its immediate leftward or upward or right-upward antidiagonal neighbors 1
2, 11, 76, 520, 3552, 24256, 165632, 1131008, 7723008, 52736000, 360103936, 2458943488, 16790716416, 114654183424, 782907736064, 5346028421120, 36504965480448, 249271496474624, 1702132247953408, 11622886011830272 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A209100

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) -8*a(n-2) for n>3

EXAMPLE

Some solutions for n=4

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

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

CROSSREFS

Sequence in context: A220878 A049363 A055085 * A118802 A053481 A110329

Adjacent sequences:  A209098 A209099 A209100 * A209102 A209103 A209104

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 05 2012

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified May 27 00:21 EDT 2017. Contains 287189 sequences.