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%I #27 Oct 15 2015 16:52:22
%S 2048,3072,4608,5120,6912,7168,7680,10368,10752,11264,11520,12800,
%T 13312,15552,16128,16896,17280,17408,17920,19200,19456,19968,23328,
%U 23552,24192,25088,25344,25920,26112,26880,28160,28800,29184,29696
%N 11-almost primes (generalization of semiprimes).
%C Product of 11 not necessarily distinct primes.
%C Divisible by exactly 11 prime powers (not including 1).
%H D. W. Wilson, <a href="/A069272/b069272.txt">Table of n, a(n) for n = 1..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/AlmostPrime.html">Almost Prime.</a>
%F Product p_i^e_i with Sum e_i = 11.
%F a(n) ~ 3628800n log n / (log log n)^10. - _Charles R Greathouse IV_, May 06 2013
%t Select[Range[9000], Plus @@ Last /@ FactorInteger[ # ] == 11 &] (* _Vladimir Joseph Stephan Orlovsky_, Apr 23 2008 *)
%t Select[Range[30000],PrimeOmega[#]==11&] (* _Harvey P. Dale_, Jul 13 2013 *)
%o (PARI) k=11; start=2^k; finish=30000; v=[] for(n=start,finish, if(bigomega(n)==k,v=concat(v,n))); v
%o (PARI) is(n)=bigomega(n)==11 \\ _Charles R Greathouse IV_, Oct 15 2015
%Y Sequences listing r-almost primes, that is, the n such that A001222(n) = r: A000040 (r = 1), A001358 (r = 2), A014612 (r = 3), A014613 (r = 4), A014614 (r = 5), A046306 (r = 6), A046308 (r = 7), A046310 (r = 8), A046312 (r = 9), A046314 (r = 10), this sequence (r = 11), A069273 (r = 12), A069274 (r = 13), A069275 (r = 14), A069276 (r = 15), A069277 (r = 16), A069278 (r = 17), A069279 (r = 18), A069280 (r = 19), A069281 (r = 20). - _Jason Kimberley_, Oct 02 2011
%K nonn
%O 1,1
%A _Rick L. Shepherd_, Mar 12 2002
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