Triangle T(n,k) read by rows: number of Green's R-classes in the semigroup of order-preserving partial transformations (of an n-element chain) consisting of elements of height k (height(alpha) = |Im(alpha)|).

A112857

Triangle T(n,k) read by rows: number of Green's R-classes in the semigroup of order-preserving partial transformations (of an n-element chain) consisting of elements of height k (height(alpha) = |Im(alpha)|).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =1a(7) =7a(8) =5a(9) =1a(10) =1a(11) =15a(12) =17a(13) =7a(14) =1a(15) =1a(16) =31a(17) =49a(18) =31a(19) =9a(20) =1a(21) =1a(22) =63a(23) =129a(24) =111a(25) =49a(26) =11a(27) =1a(28) =1a(29) =127

External references