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A203371
T(n,k)=Number of nXk 0..2 arrays with every 1 immediately preceded by 0 to the left or above, and every 2 immediately preceded by both a 1 and a 0
8
1, 2, 2, 3, 9, 3, 5, 30, 30, 5, 8, 110, 206, 110, 8, 13, 390, 1570, 1570, 390, 13, 21, 1399, 11541, 25087, 11541, 1399, 21, 34, 4998, 85932, 386353, 386353, 85932, 4998, 34, 55, 17881, 636912, 6026844, 12450511, 6026844, 636912, 17881, 55, 89, 63940, 4728287
OFFSET
1,2
COMMENTS
Table starts
..1.....2.......3..........5............8..............13................21
..2.....9......30........110..........390............1399..............4998
..3....30.....206.......1570........11541...........85932............636912
..5...110....1570......25087.......386353.........6026844..........93584344
..8...390...11541.....386353.....12450511.......406389748.......13204707603
.13..1399...85932....6026844....406389748.....27758308569.....1887519232797
.21..4998..636912...93584344..13204707603...1887519232797...268596415269518
.34.17881.4728287.1455532600.429752891417.128552812110552.38282460992672716
LINKS
EXAMPLE
Some solutions for n=4 k=3
..0..1..0....0..0..1....0..0..1....0..0..1....0..0..1....0..1..0....0..0..0
..1..0..0....0..0..2....0..0..2....0..0..2....0..0..0....1..0..1....0..0..0
..0..1..0....0..0..0....1..0..0....0..0..0....0..0..0....0..0..1....0..0..0
..0..0..1....0..0..0....0..0..1....0..0..1....0..0..0....1..1..0....1..2..0
CROSSREFS
Column 1 is A000045(n+1)
Sequence in context: A252848 A241475 A132812 * A181206 A274959 A143307
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Dec 31 2011
STATUS
approved