Denominator of z-sequence for Sheffer triangle A060081.

Terms

a(0) =1a(1) =2a(2) =1a(3) =4a(4) =1a(5) =6a(6) =1a(7) =24a(8) =1a(9) =10a(10) =1a(11) =12a(12) =1a(13) =210a(14) =1a(15) =48a(16) =1a(17) =90a(18) =1a(19) =420a(20) =1a(21) =330a(22) =1a(23) =360a(24) =1a(25) =1638a(26) =1a(27) =28a(28) =1a(29) =30