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 A172421 #11 Sep 04 2023 16:36:14
%S A172421 128,256,512,1024,2048,2187,4096,6561,8192,16384,19683,32768,49152,
%T A172421 52488,55296,59049,62208,65536,69984,73728,78125,78732,82944,93312,
%U A172421 98304,104976,110592,118098,124416,131072,139968,147456,157464,165888,177147,186624,196608
%N A172421 Numbers k that have measure of smoothness J larger than 6, where J = log(k)/log(rad(k)) and rad(k) is the product of the distinct prime divisors of k (A007947).
%C A172421 This sequence is a subsequence of A049094, A172418, A172419, and A172420.
%H A172421 Amiram Eldar, <a href="/A172421/b172421.txt">Table of n, a(n) for n = 1..1000</a>
%t A172421 aa = {}; Do[kk = FactorInteger[c]; nn = 1; Do[nn = nn*kk[[n]][[1]], {n, 1, Length[kk]}]; If[Log[c]/Log[nn] > 6, AppendTo[aa, c]], {c, 2, 10000}]; aa
%Y A172421 Cf. A007947, A049094, A059172, A172418, A172419, A172420, A172422.
%K A172421 nonn
%O A172421 1,1
%A A172421 _Artur Jasinski_, Feb 02 2010
%E A172421 More terms from _Amiram Eldar_, Mar 10 2020