A305823 Total number of blocks in all set partitions of [n] with alternating parity of elements.

0, 1, 3, 8, 20, 53, 136, 383, 1067, 3292, 10162, 34586, 118332, 441898, 1660947, 6745710, 27575425, 120801230, 532530170, 2499230441, 11800052796, 58992236094, 296630364605, 1572128197439, 8378539879636, 46882666240016, 263735138346443, 1552510947814406

Offset: 0

Author

Alois P. Heinz, Jun 10 2018

Keywords

• nonn

Links

• Wikipedia, Partition of a set

Crossrefs

Cf. A274581.

Formula

a(n) = Sum_{k=0..n} k * A274581(n,k).