A122980 Number of distributive sublattices of the lattice of k-tuples less than the n-th partition (in Mathematica order), that include the maximum element.

2, 4, 7, 8, 21, 45, 16, 58, 84, 200, 500, 32, 152, 293, 748, 1184, 3220

Offset: 1

Author

Franklin T. Adams-Watters, Sep 21 2006

Keywords

• nonn
• more

Comments

After a(18) - for partition [1^5] - the sequence continues ?, 64, 384, 938, 2520, 1238, 5591, ?, ?, ?, ?, ?, 128.

Examples

			For a(5), partition [2,1], the lattice consists of the 6 pairs (i,j) where 0<=i<=2 and 0<=j<=1, with (i,j) <= (i',j') iff i<=i' and j<=j'. {(2,1), (2,0), (0,1), (0,0)} is one distributive sublattice.
		

Crossrefs

Cf. A122977, A122979, A122982, A080577, A074139.