Cancellation factor in reducing Sum_{k=0...n} 1/k! to lowest terms.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =1a(5) =2a(6) =1a(7) =20a(8) =1a(9) =10a(10) =1a(11) =8a(12) =5a(13) =2a(14) =5a(15) =4a(16) =1a(17) =130a(18) =1a(19) =4000a(20) =1a(21) =2a(22) =5a(23) =52a(24) =5a(25) =494a(26) =1a(27) =40a(28) =1a(29) =10