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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
OFFSET
1,1
COMMENTS
This sequence is a subsequence of A049094, A172418, A172419, and A172420.
LINKS
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
KEYWORD
nonn
AUTHOR
Artur Jasinski, Feb 02 2010
EXTENSIONS
More terms from Amiram Eldar, Mar 10 2020
STATUS
approved