cp's OEIS Frontend

A269736 Triangle read by rows: T(n,r) (0 <= r <= n) = number of idempotents of rank r in the Motzkin monoid M_n.

%I A269736 #11 Apr 15 2016 13:44:27
%S A269736 1,1,1,4,2,1,16,11,3,1,81,48,19,4,1,441,266,93,28,5,1,2601,1492,549,
%T A269736 152,38,6,1,16129,9042,3211,947,226,49,7,1
%N A269736 Triangle read by rows: T(n,r) (0 <= r <= n) = number of idempotents of rank r in the Motzkin monoid M_n.
%H A269736 I. Dolinka, J. East et al, <a href="http://arxiv.org/abs/1507.04838">Idempotent Statistics of the Motzkin and Jones Monoids</a>, arXiv: 1507.04838 (2015), Table 2.
%e A269736 Triangle begins:
%e A269736 1,
%e A269736 1,1,
%e A269736 4,2,1,
%e A269736 16,11,3,1,
%e A269736 81,48,19,4,1,
%e A269736 441,266,93,28,5,1,
%e A269736 2601,1492,549,152,38,6,1,
%e A269736 16129,9042,3211,947,226,49,7,1,
%e A269736 ...
%Y A269736 First column is A001006(n)^2.
%Y A269736 Row sums are A256672.
%K A269736 nonn,tabl,more
%O A269736 0,4
%A A269736 _N. J. A. Sloane_, Mar 13 2016