Triangle of coefficients of certain Sheffer-polynomials.

Terms

a(0) =1a(1) =1a(2) =1a(3) =4a(4) =10a(5) =1a(6) =30a(7) =132a(8) =27a(9) =1a(10) =336a(11) =2232a(12) =696a(13) =52a(14) =1a(15) =5040a(16) =46320a(17) =19500a(18) =2200a(19) =85a(20) =1a(21) =95040a(22) =1141920a(23) =606960a(24) =91800a(25) =5340a(26) =126a(27) =1a(28) =2162160a(29) =32639040