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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

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Last modified September 1 20:00 EDT 2014. Contains 246317 sequences.