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

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

R. H. Hardin, Table of n, a(n) for n = 1..442

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

Adjacent sequences: A203368 A203369 A203370 * A203372 A203373 A203374

Keyword

nonn,tabl

Author

R. H. Hardin Dec 31 2011

Status

approved