a(1) = 1; a(n+1) = Product_{d|n} (1 + a(d)).

A333121

a(1) = 1; a(n+1) = Product_{d|n} (1 + a(d)).

Terms

    a(0) =1a(1) =2a(2) =6a(3) =14a(4) =90a(5) =182a(6) =7686a(7) =15374a(8) =1383750a(9) =19372514a(10) =10577393190a(11) =21154786382

External references