Sheffer triangle S2[4,1] = (exp(x), exp(4*x) - 1).

Terms

a(0) =1a(1) =1a(2) =4a(3) =1a(4) =24a(5) =16a(6) =1a(7) =124a(8) =240a(9) =64a(10) =1a(11) =624a(12) =2656a(13) =1792a(14) =256a(15) =1a(16) =3124a(17) =26400a(18) =33920a(19) =11520a(20) =1024a(21) =1a(22) =15624a(23) =250096a(24) =546560a(25) =331520a(26) =67584a(27) =4096a(28) =1a(29) =78124