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 A069278 17-almost primes (generalization of semiprimes). 27
 131072, 196608, 294912, 327680, 442368, 458752, 491520, 663552, 688128, 720896, 737280, 819200, 851968, 995328, 1032192, 1081344, 1105920, 1114112, 1146880, 1228800, 1245184, 1277952, 1492992, 1507328, 1548288, 1605632, 1622016 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Product of 17 not necessarily distinct primes. Divisible by exactly 17 prime powers (not including 1). For n = 1..2628 a(n)=2*A069277(n). - Zak Seidov, Jun 25 2017 LINKS D. W. Wilson, Table of n, a(n) for n = 1..10000 Eric Weisstein's World of Mathematics, Almost Prime. FORMULA Product p_i^e_i with Sum e_i = 17. MATHEMATICA Select[Range[2*10^6], PrimeOmega[#]==17&] (* Harvey P. Dale, Sep 28 2016 *) PROG (PARI) k=17; start=2^k; finish=2000000; v=[] for(n=start, finish, if(bigomega(n)==k, v=concat(v, n))); v CROSSREFS 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 Sequence in context: A069392 A289479 A222529 * A190780 A017698 A010805 Adjacent sequences:  A069275 A069276 A069277 * A069279 A069280 A069281 KEYWORD nonn AUTHOR Rick L. Shepherd, Mar 13 2002 STATUS approved

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Last modified April 1 14:18 EDT 2020. Contains 333159 sequences. (Running on oeis4.)