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%I #15 May 31 2020 02:18:22
%S 27000,74088,189000,287496,297000,343000,351000,370440,459000,474552,
%T 513000,621000,783000,814968,837000,963144,999000,1029000,1061208,
%U 1107000,1157625,1161000,1259496,1269000,1323000,1331000,1407672,1431000,1437480,1481544,1593000,1647000,1704024,1809000,1852200,1917000,1971000,2012472,2079000,2133000,2148552
%N Numbers with at least three 3s in their prime signature.
%C In other words, if the canonical prime factorization of n into prime powers is Product p(i)^e(i), then e(i) = 3 for at least three values of i.
%H Amiram Eldar, <a href="/A176359/b176359.txt">Table of n, a(n) for n = 1..10000</a>
%e 27000 is a term since 27000 = 2^3 * 3^3 * 5^3.
%e 74088 is a term since 74088 = 2^3 * 5^3 * 7^3.
%t f[n_]:=Count[Last/@FactorInteger[n],3]>2; Select[Range[10!],f]
%Y Cf. A000578, A001235, A176297, A176313, A176350, A109399.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Dec 07 2010
%E Edited by _Matthew Vandermast_, Dec 09 2010
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