A256038 Triangle read by rows: number of R-class idempotent basis elements of rank k in Brauer monoid B_n.

1, 0, 1, 0, 0, 1, 0, 2, 0, 1, 0, 0, 4, 0, 1, 0, 8, 0, 6, 0, 1, 0, 0, 24, 0, 8, 0, 1, 0, 48, 0, 48, 0, 10, 0, 1, 0, 0, 192, 0, 80, 0, 12, 0, 1, 0, 384, 0, 480, 0, 120, 0, 14, 0, 1, 0, 0, 1920, 0, 168, 0, 195, 0, 16, 0, 1

Offset

0,8

Links

Table of n, a(n) for n=0..65.

I. Dolinka, J. East, A. Evangelou, D. FitzGerald, N. Ham, et al., Enumeration of idempotents in diagram semigroups and algebras, arXiv preprint arXiv:1408.2021 [math.GR], 2014.

Example

Triangle begins:
1,
0, 1,
0, 0, 1,
0, 2, 0, 1,
0, 0, 4, 0, 1,
0, 8, 0, 6, 0, 1,
0, 0, 24, 0, 8, 0, 1,
0, 48, 0, 48, 0, 10, 0, 1,
0, 0, 192, 0, 80, 0, 12, 0, 1,
0, 384, 0, 480, 0, 120, 0, 14, 0, 1,
0, 0, 1920, 0, 168, 0, 195, 0, 16, 0, 1,
...

Crossrefs

Sequence in context: A352996 A329918 A281442 * A050327 A075120 A327751

Adjacent sequences: A256035 A256036 A256037 * A256039 A256040 A256041

Keyword

nonn,tabl

Author

N. J. A. Sloane, Mar 14 2015

Status

approved