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
Offset: 0
Examples
Triangle begins: 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, ...
Links
- I. Dolinka, J. East et al, Idempotent Statistics of the Motzkin and Jones Monoids, arXiv: 1507.04838 (2015), Table 2.