A271467 Number of set partitions of [2n] such that n is the largest element of the last block.

0, 1, 10, 149, 3149, 88772, 3195161, 142084077, 7611839904, 481614364251, 35417157810681, 2987457716884346, 285867917955683723, 30741794345071162069, 3685435185993122202106, 489101076818110701758097, 71414666988339306082779537, 11410190978037926887950636172

Offset

1,3

Comments

Each set partition is written as a sequence of blocks, ordered by the smallest elements in the blocks.

Links

Alois P. Heinz, Table of n, a(n) for n = 1..200

Wikipedia, Partition of a set

Formula

a(n) = A271466(2n,n).

Example

a(2) = 1: 134|2.
a(3) = 10: 12456|3, 1456|23, 1456|2|3, 145|26|3, 146|25|3, 14|256|3, 156|24|3, 15|246|3, 16|245|3, 1|2456|3.

Crossrefs

Cf. A271466.

Sequence in context: A178084 A098270 A262738 * A212471 A157867 A116156

Adjacent sequences: A271464 A271465 A271466 * A271468 A271469 A271470

Keyword

nonn

Author

Alois P. Heinz, Apr 08 2016

Status

approved