A210545 T(n,k) = number of arrays of n nonnegative integers with value i>0 appearing only after i-1 has appeared at least k times.

1, 1, 2, 1, 1, 5, 1, 1, 2, 15, 1, 1, 1, 4, 52, 1, 1, 1, 2, 9, 203, 1, 1, 1, 1, 4, 23, 877, 1, 1, 1, 1, 2, 8, 65, 4140, 1, 1, 1, 1, 1, 4, 17, 199, 21147, 1, 1, 1, 1, 1, 2, 8, 40, 654, 115975, 1, 1, 1, 1, 1, 1, 4, 16, 104, 2296, 678570, 1, 1, 1, 1, 1, 1, 2, 8, 33, 291, 8569, 4213597, 1, 1, 1, 1

Offset: 1

Author

R. H. Hardin, Mar 22 2012

Keywords

• nonn
• tabl

Examples

			Some solutions for n=13 k=4
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....1....1....1....1....0....0....1....0....0....1....1....0....1....1
..0....0....1....1....1....1....1....0....0....0....1....1....0....1....1....0
..1....0....0....1....1....1....0....1....1....0....0....0....0....1....1....0
..0....1....1....0....1....1....0....1....0....0....1....0....0....1....1....1
..1....1....0....0....1....2....1....1....0....1....1....0....0....1....2....1
..0....1....0....1....0....1....1....1....1....0....1....1....1....1....2....1
..0....1....0....2....1....0....0....1....1....0....2....0....1....1....2....1
..1....2....0....1....1....0....1....0....0....1....1....0....0....2....1....0
..0....2....1....0....2....0....0....0....2....1....2....1....0....0....0....1
Table starts
..........1.......1......1.....1....1...1...1
..........2.......1......1.....1....1...1...1
..........5.......2......1.....1....1...1...1
.........15.......4......2.....1....1...1...1
.........52.......9......4.....2....1...1...1
........203......23......8.....4....2...1...1
........877......65.....17.....8....4...2...1
.......4140.....199.....40....16....8...4...2
......21147.....654....104....33...16...8...4
.....115975....2296....291....73...32..16...8
.....678570....8569....857...177...65..32..16
....4213597...33825...2634...467..138..64..32
...27644437..140581...8455..1309..315.129..64
..190899322..612933..28424..3813..782.267.128
.1382958545.2795182.100117.11409.2090.582.257
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..9999
• Rigoberto Flórez, José L. Ramírez, Fabio A. Velandia, and Diego Villamizar, Some Connections Between Restricted Dyck Paths, Polyominoes, and Non-Crossing Partitions, arXiv:2308.02059 [math.CO], 2023. See Table 1 p. 13.

Crossrefs

Cf. A000110 (column 1), A007476 (column 2), A210540 (column 3).

Formula

T(n,k)=1 if n<=k else Sum_{i=0..n-k} binomial(n-k,i)*T(i,k). Proved by R. J. Mathar in the Sequence Fans Mailing List.