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.

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

Author

R. H. Hardin, Dec 30 2011

Keywords

• nonn
• tabl

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

Examples

			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
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..364

Crossrefs

Column 1 is A000931(n+5). Column 2 is A203175.