A202756 T(n,k)=Number of nXk nonnegative integer arrays with each row and column increasing from zero by 0 or 1.
1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 4, 8, 4, 1, 1, 5, 17, 17, 5, 1, 1, 6, 31, 62, 31, 6, 1, 1, 7, 51, 184, 184, 51, 7, 1, 1, 8, 78, 462, 924, 462, 78, 8, 1, 1, 9, 113, 1022, 3809, 3809, 1022, 113, 9, 1, 1, 10, 157, 2052, 13197, 26394, 13197, 2052, 157, 10, 1, 1, 11, 211, 3819, 39675
Offset: 1
Examples
Some solutions for n=5 k=3 ..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....0..0..0....0..1..1....0..1..1....0..0..0....0..0..0 ..0..0..1....0..0..1....0..0..0....0..1..1....0..1..2....0..0..0....0..0..0 ..0..0..1....0..1..1....0..0..1....0..1..2....0..1..2....0..0..0....0..0..0 ..0..0..1....0..1..2....0..1..1....0..1..2....0..1..2....0..1..1....0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..684
Crossrefs
Column 3 is A105163(n+1)
Formula
Empirical: Columns of T(n,k) are a polynomial in n of degree k*(k-1)/2.
For elements increasing by 0..d instead of 0..1, columns are a polynomial of degree d*k*(k-1)/2.
Comments