A280885 Number of set partitions of [n] into exactly seven blocks where sizes of distinct blocks are coprime.

1, 28, 84, 2730, 462, 45276, 73788, 2849847, 365365, 69293224, 4913272, 623100660, 1424294340, 67844069880, 333126696, 2369968906305, 38838853515, 4030108023172, 3637504185700, 767066790520030, 21258921662550, 13536000500234940, 10485013256679780

Offset

7,2

Links

Table of n, a(n) for n=7..29.

Wikipedia, Coprime integers

Wikipedia, Partition of a set

Crossrefs

Column k=7 of A280880.

Sequence in context: A306427 A254145 A271735 * A042542 A042540 A042544

Adjacent sequences: A280882 A280883 A280884 * A280886 A280887 A280888

Keyword

nonn

Author

Alois P. Heinz, Jan 09 2017

Status

approved