Triangle read by rows, the Bell transform of n!*binomial(2,n) (without column 0).

Terms

a(0) =1a(1) =2a(2) =1a(3) =2a(4) =6a(5) =1a(6) =0a(7) =20a(8) =12a(9) =1a(10) =0a(11) =40a(12) =80a(13) =20a(14) =1a(15) =0a(16) =40a(17) =360a(18) =220a(19) =30a(20) =1a(21) =0a(22) =0a(23) =1120a(24) =1680a(25) =490a(26) =42a(27) =1a(28) =0a(29) =0