Triangle of transformation semigroup sizes generated by a single element.

Terms

a(0) =1a(1) =1a(2) =3a(3) =1a(4) =10a(5) =15a(6) =2a(7) =41a(8) =129a(9) =80a(10) =6a(11) =196a(12) =1115a(13) =1260a(14) =510a(15) =24a(16) =20a(17) =1057a(18) =10395a(19) =17780a(20) =12840a(21) =3744a(22) =840a(23) =6322a(24) =105315a(25) =258510a(26) =264810a(27) =135492a(28) =47250a(29) =4920