a(1) = 1; for n >= 2, suppose a(n-1) = Product p_i^e_i and n = Product p_i^f_i, then a(n) = Product p_i^(e_i*f_i).
A072181
a(1) = 1; for n >= 2, suppose a(n-1) = Product p_i^e_i and n = Product p_i^f_i, then a(n) = Product p_i^(e_i*f_i).
Terms
- a(0) =1a(1) =2a(2) =6a(3) =12a(4) =60a(5) =60a(6) =420a(7) =6720a(8) =20160a(9) =20160a(10) =221760a(11) =14192640a(12) =184504320a(13) =184504320a(14) =184504320
External references
- oeis: A072181