Triangle read by rows. First in a series of triangular arrays counting permutations of partitions.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =1a(6) =6a(7) =8a(8) =6a(9) =1a(10) =24a(11) =30a(12) =20a(13) =10a(14) =1a(15) =120a(16) =144a(17) =90a(18) =40a(19) =15a(20) =1a(21) =720a(22) =840a(23) =504a(24) =210a(25) =70a(26) =21a(27) =1a(28) =5040a(29) =5760