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A203181
T(n,k) is the number of n X k 0..2 arrays with every 1 immediately preceded by 0 to the left or above, no 0 immediately preceded by a 0, and every 2 immediately preceded by 0 1 to the left or above.
8
1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 3, 4, 7, 4, 3, 4, 6, 17, 17, 6, 4, 5, 10, 41, 59, 41, 10, 5, 7, 18, 97, 205, 205, 97, 18, 7, 9, 30, 235, 724, 952, 724, 235, 30, 9, 12, 50, 607, 2466, 4654, 4654, 2466, 607, 50, 12, 16, 86, 1415, 8948, 23083, 32411, 23083, 8948, 1415, 86, 16, 21, 146
OFFSET
1,4
COMMENTS
Table starts
.1..1...2....2......3.......4........5.........7..........9..........12
.1..1...2....4......6......10.......18........30.........50..........86
.2..2...7...17.....41......97......235.......607.......1415........3486
.2..4..17...59....205.....724.....2466......8948......30945......108083
.3..6..41..205....952....4654....23083....115377.....551208.....2757161
.4.10..97..724...4654...32411...223567...1625772...10889470....76035931
.5.18.235.2466..23083..223567..2208945..22411843..216858412..2141041521
.7.30.607.8948.115377.1625772.22411843.323885934.4389100997.61921804090
LINKS
EXAMPLE
Some solutions for n=5 k=3
..0..1..0....0..1..2....0..1..0....0..1..0....0..1..2....0..1..0....0..1..2
..1..0..1....1..0..1....1..0..1....1..0..1....1..0..1....1..0..1....1..0..1
..2..1..2....2..1..0....2..1..2....0..1..0....0..1..2....0..1..2....0..1..0
..0..1..2....0..1..2....0..1..0....1..2..1....1..2..0....1..2..0....1..2..1
..1..0..1....1..0..1....1..0..1....2..0..1....0..1..1....0..1..1....2..0..1
CROSSREFS
Column 1 is A000931(n+5). Column 2 is A203175.
Sequence in context: A105223 A025859 A031281 * A113793 A289499 A215904
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Dec 30 2011
STATUS
approved