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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). 5
128, 256, 512, 1024, 2048, 2187, 4096, 6561, 8192, 16384, 19683, 32768, 49152, 52488, 55296, 59049, 62208, 65536, 69984, 73728, 78125, 78732, 82944, 93312, 98304, 104976, 110592, 118098, 124416, 131072, 139968, 147456, 157464, 165888, 177147, 186624, 196608 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence is subset of A049094 and A172418 and A172419 and A172420.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000

MATHEMATICA

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

CROSSREFS

Cf. A007947, A049094, A059172, A172418, A172419, A172420, A172422.

Sequence in context: A045028 A255997 A256821 * A235059 A045053 A234877

Adjacent sequences:  A172418 A172419 A172420 * A172422 A172423 A172424

KEYWORD

nonn

AUTHOR

Artur Jasinski, Feb 02 2010

EXTENSIONS

More terms from Amiram Eldar, Mar 10 2020

STATUS

approved

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Last modified October 27 15:27 EDT 2021. Contains 348287 sequences. (Running on oeis4.)