A320615 Number of ordered set partitions of [n] where k = two is minimal such that for each block b the smallest integer interval containing b has at most k elements.

1, 4, 20, 114, 750, 5616, 47304, 443400, 4582200, 51790320, 635791680, 8426915280, 119960552880, 1825701857280, 29585590473600, 508653914267520, 9248148480574080, 177303557272262400, 3574966680853747200, 75628468328518828800, 1675003757666567328000

Offset

2,2

Links

Alois P. Heinz, Table of n, a(n) for n = 2..450

Crossrefs

Column k=2 of A276891.

Sequence in context: A346414 A028475 A128327 * A316298 A291531 A171802

Adjacent sequences: A320612 A320613 A320614 * A320616 A320617 A320618

Keyword

nonn

Author

Alois P. Heinz, Oct 17 2018

Status

approved