A269736 - OEIS

A269736

Triangle read by rows: T(n,r) (0 <= r <= n) = number of idempotents of rank r in the Motzkin monoid M_n.

1, 1, 1, 4, 2, 1, 16, 11, 3, 1, 81, 48, 19, 4, 1, 441, 266, 93, 28, 5, 1, 2601, 1492, 549, 152, 38, 6, 1, 16129, 9042, 3211, 947, 226, 49, 7, 1

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

I. Dolinka, J. East et al, Idempotent Statistics of the Motzkin and Jones Monoids, arXiv: 1507.04838 (2015), Table 2.

EXAMPLE

Triangle begins:

1,1,

4,2,1,

16,11,3,1,

81,48,19,4,1,

441,266,93,28,5,1,

2601,1492,549,152,38,6,1,

16129,9042,3211,947,226,49,7,1,

...

CROSSREFS

First column is A001006(n)^2.

Row sums are A256672.

KEYWORD

nonn,tabl,more

AUTHOR

STATUS

approved