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 A051270 Numbers that are divisible by exactly 5 different primes. 22
 2310, 2730, 3570, 3990, 4290, 4620, 4830, 5460, 5610, 6006, 6090, 6270, 6510, 6630, 6930, 7140, 7410, 7590, 7770, 7854, 7980, 8190, 8580, 8610, 8778, 8970, 9030, 9240, 9282, 9570, 9660, 9690, 9870, 10010, 10230, 10374, 10626, 10710, 10920, 11130 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 EXAMPLE 2730 = 2*3*5*7*13 is the first nontrivial 5-prime factor number following the 5th primorial, 2310 = 2*3*5*7*11. MAPLE A051270 := proc(n)     option remember;     local a;     if n = 1 then         2*3*5*7*11 ;     else         for a from procname(n-1)+1 do             if A001221(a)= 5 then                 return a;             end if;         end do:     end if; end proc: # R. J. Mathar, Oct 13 2019 MATHEMATICA lst={}; Do[If[Length[FactorInteger[n]]==5, (*Print[n]; *)AppendTo[lst, n]], {n, 3*10^4}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 21 2008 *) Select[Range[12000], PrimeNu[#]==5&] (* Harvey P. Dale, Feb 13 2012 *) PROG (PARI) is(n)=omega(n)==5 \\ Charles R Greathouse IV, Apr 29 2015 (Python) from sympy import primefactors print [n for n in xrange(2, 20001) if len(primefactors(n))==5] # Indranil Ghosh, Apr 06 2017 CROSSREFS Cf. A000961, A007774, A000977, A002110, A033992, A033993. Cf. A046303 (a subsequence). - Michel Marcus, Apr 06 2017 Sequence in context: A060231 A285487 A285744 * A046387 A136154 A258360 Adjacent sequences:  A051267 A051268 A051269 * A051271 A051272 A051273 KEYWORD nonn,changed AUTHOR STATUS approved

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Last modified October 14 00:08 EDT 2019. Contains 327990 sequences. (Running on oeis4.)