This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A387141 #9 Aug 18 2025 18:50:46
%S A387141 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,
%T A387141 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,
%U A387141 13,13,13,14,14,13,14,14,14,15,15,15,16,15,16,16
%N 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.
%F A387141 a(n) = floor(A048803(n)^(1/n)) for n >= 1.
%p A387141 a := n -> if n = 0 then 1 else floor(mul(NumberTheory:-Radical(k), k = 1..n)^(1/n)) fi:
%t A387141 A387141[n_] := If[n == 0, 1, Floor[Power[Times @@ ResourceFunction["IntegerRadical"][Range[1, n]], 1/n]]]; Table[A387141[n], {n, 0, 74}]
%Y A387141 Cf. A007947, A048803, A387140.
%K A387141 nonn
%O A387141 0,6
%A A387141 _Peter Luschny_, Aug 18 2025