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A172419 Numbers c that have measure of smoothness J bigger than 4, where J = log(c)/log(N(c)) and N(c) is the product of the distinct prime divisors of c. 4

%I

%S 32,64,128,243,256,512,729,1024,1458,1536,1728,1944,2048,2187,2304,

%T 2592,2916,3072,3125,3456,3888,4096,4374,4608,5184,5832,6144,6561,

%U 6912,7776,8192,8748,9216,10240,10368,11664,12288,12500,12800,13122,13824,15552

%N Numbers c that have measure of smoothness J bigger than 4, where J = log(c)/log(N(c)) and N(c) is the product of the distinct prime divisors of c.

%C Subsequence of A049094 and A172418.

%p aa = {}; Do[kk = FactorInteger[c]; nn = 1; Do[nn = nn*kk[[n]][[1]], {n, 1, Length[kk]}]; If[Log[c]/Log[nn] > 4, AppendTo[aa, c]], {c, 2, 10000}]; aa # _Artur Jasinski_

%Y Cf. A049094, A172418, A172420, A172421, A172422.

%K nonn

%O 1,1

%A _Artur Jasinski_, Feb 02 2010

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Last modified December 10 23:07 EST 2016. Contains 279021 sequences.