A286433 Number of entries in the second last blocks of all set partitions of [n].

1, 6, 25, 98, 399, 1746, 8271, 42284, 231939, 1357128, 8427181, 55288860, 381798629, 2765917074, 20960284277, 165729739590, 1364153612299, 11665484410094, 103448316470723, 949739632313480, 9013431476894623, 88304011710168668, 891917738589610553

Offset: 2

Author

Alois P. Heinz, May 09 2017

Keywords

• nonn

Examples

			a(3) = 6 because the number of entries in the second last blocks of all set partitions of [3] (123, 12|3, 13|2, 1|23, 1|2|3) is 0+2+2+1+1 = 6.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 2..250
• Wikipedia, Partition of a set

Crossrefs

Column k=2 of A286416.