1, followed by denominators of first differences of Bernoulli numbers (B(i)-B(i-1)).

Terms

a(0) =1a(1) =2a(2) =3a(3) =6a(4) =30a(5) =30a(6) =42a(7) =42a(8) =30a(9) =30a(10) =66a(11) =66a(12) =2730a(13) =2730a(14) =6a(15) =6a(16) =510a(17) =510a(18) =798a(19) =798a(20) =330a(21) =330a(22) =138a(23) =138a(24) =2730a(25) =2730a(26) =6a(27) =6a(28) =870a(29) =870