Numbers of the form Bell(i)*Bell(j).

Terms

a(0) =1a(1) =2a(2) =4a(3) =5a(4) =10a(5) =15a(6) =25a(7) =30a(8) =52a(9) =75a(10) =104a(11) =203a(12) =225a(13) =260a(14) =406a(15) =780a(16) =877a(17) =1015a(18) =1754a(19) =2704a(20) =3045a(21) =4140a(22) =4385a(23) =8280a(24) =10556a(25) =13155a(26) =20700a(27) =21147a(28) =41209a(29) =42294