A223961 T(n,k)=Number of nXk 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.
4, 10, 16, 20, 85, 64, 35, 295, 707, 256, 56, 805, 3471, 5864, 1024, 84, 1876, 12311, 41006, 48620, 4096, 120, 3906, 36028, 176893, 485714, 403104, 16384, 165, 7470, 92734, 594286, 2575955, 5777663, 3342081, 65536, 220, 13365, 217144, 1718057
Offset: 1
Examples
Some solutions for n=3 k=4 ..1..2..2..3....1..2..2..2....0..0..2..2....0..0..1..1....0..1..1..3 ..0..2..2..2....1..3..3..3....1..3..3..3....1..2..2..2....0..1..1..1 ..0..0..3..3....0..2..3..3....0..3..3..3....1..2..3..3....1..1..2..3
Links
- R. H. Hardin, Table of n, a(n) for n = 1..287
Formula
Empirical: columns k=1..5 have recurrences of order 1,4,13,34,63 for n>0,0,0,36,68
Empirical rows n=1..7 are polynomials of order 3*n for k>0,0,2,5,8,11,14
Comments