A387141 a(n) = floor((Product_{k=1..n} radical(k))^(1/n)) for n >= 1, a(0) = 1, where radical(n) is the product of distinct prime factors of n, cf. A007947.

1, 1, 1, 1, 1, 2, 2, 3, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 8, 7, 8, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 13, 14, 14, 14, 15, 15, 15, 16, 15, 16, 16

Offset: 0

Author

Peter Luschny, Aug 18 2025

Keywords

• nonn

Crossrefs

Cf. A007947, A048803, A387140.

Programs

Maple

a := n -> if n = 0 then 1 else floor(mul(NumberTheory:-Radical(k), k = 1..n)^(1/n)) fi:

Mathematica

A387141[n_] := If[n == 0, 1, Floor[Power[Times @@ ResourceFunction["IntegerRadical"][Range[1, n]], 1/n]]]; Table[A387141[n], {n, 0, 74}]

Formula

a(n) = floor(A048803(n)^(1/n)) for n >= 1.