a(n) = Product_{k=1..n} rad(k), where rad(n) is the product of distinct prime factors of n, cf. A007947.

A048803

a(n) = Product_{k=1..n} rad(k), where rad(n) is the product of distinct prime factors of n, cf. A007947.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =12a(5) =60a(6) =360a(7) =2520a(8) =5040a(9) =15120a(10) =151200a(11) =1663200a(12) =9979200a(13) =129729600a(14) =1816214400a(15) =27243216000a(16) =54486432000a(17) =926269344000

External references