Triangle of generalized Stirling numbers.

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =9a(5) =6a(6) =1a(7) =34a(8) =72a(9) =24a(10) =1a(11) =125a(12) =650a(13) =600a(14) =120a(15) =1a(16) =461a(17) =5400a(18) =10500a(19) =5400a(20) =720a(21) =1a(22) =1715a(23) =43757a(24) =161700a(25) =161700a(26) =52920a(27) =5040a(28) =1a(29) =6434