Triangle T(n,k) defined by Sum_{k=1..n} T(n,k)*u^k*x^n/n! = exp(Sum_{n>0} u*sigma(n)*x^n/n!).

Terms

a(0) =1a(1) =3a(2) =1a(3) =4a(4) =9a(5) =1a(6) =7a(7) =43a(8) =18a(9) =1a(10) =6a(11) =155a(12) =175a(13) =30a(14) =1a(15) =12a(16) =511a(17) =1230a(18) =485a(19) =45a(20) =1a(21) =8a(22) =1442a(23) =7231a(24) =5600a(25) =1085a(26) =63a(27) =1a(28) =15a(29) =4131