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

0,6

Links

Table of n, a(n) for n=0..74.

Formula

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

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}]

Crossrefs

Cf. A007947, A048803, A387140.

Sequence in context: A334796 A140361 A237769 * A187182 A362816 A176208

Adjacent sequences: A387138 A387139 A387140 * A387142 A387143 A387144

Keyword

nonn

Author

Peter Luschny, Aug 18 2025

Status

approved