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%I #28 Jun 25 2017 19:03:29
%S 131072,196608,294912,327680,442368,458752,491520,663552,688128,
%T 720896,737280,819200,851968,995328,1032192,1081344,1105920,1114112,
%U 1146880,1228800,1245184,1277952,1492992,1507328,1548288,1605632,1622016
%N 17-almost primes (generalization of semiprimes).
%C Product of 17 not necessarily distinct primes.
%C Divisible by exactly 17 prime powers (not including 1).
%C For n = 1..2628 a(n)=2*A069277(n). - _Zak Seidov_, Jun 25 2017
%H D. W. Wilson, <a href="/A069278/b069278.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 = 17.
%t Select[Range[2*10^6],PrimeOmega[#]==17&] (* _Harvey P. Dale_, Sep 28 2016 *)
%o (PARI) k=17; start=2^k; finish=2000000; v=[] for(n=start,finish, if(bigomega(n)==k,v=concat(v,n))); v
%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), A069272 (r = 11), A069273 (r = 12), A069274 (r = 13), A069275 (r = 14), A069276 (r = 15), A069277 (r = 16), this sequence (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 13 2002
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