Triangle related to the o.g.f.s. of the right-hand columns of A028421 (E(x,m=2,n)).

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =10a(5) =3a(6) =6a(7) =52a(8) =43a(9) =4a(10) =24a(11) =308a(12) =472a(13) =136a(14) =5a(15) =120a(16) =2088a(17) =4980a(18) =2832a(19) =369a(20) =6a(21) =720a(22) =16056a(23) =53988a(24) =49808a(25) =13638a(26) =918a(27) =7a(28) =5040a(29) =138528