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 A046099 Numbers that are not cubefree. Numbers divisible by a cube greater than 1. Complement of A004709. 41
 8, 16, 24, 27, 32, 40, 48, 54, 56, 64, 72, 80, 81, 88, 96, 104, 108, 112, 120, 125, 128, 135, 136, 144, 152, 160, 162, 168, 176, 184, 189, 192, 200, 208, 216, 224, 232, 240, 243, 248, 250, 256, 264, 270, 272, 280, 288, 296, 297, 304, 312, 320, 324, 328, 336 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Also called cubeful numbers, but this term is ambiguous and is best avoided. Numbers n such that A007427(n) = sum(d|n,mu(d)*mu(n/d)) == 0. - Benoit Cloitre, Apr 17 2002 The convention in the OEIS is that squareful, cubeful, biquadrateful (A046101), ... mean the same as "not squarefree" etc., while 2- or square-full, 3- or cube-full (A036966), 4-full (A036967) are used for Golomb's notion of powerful numbers (A001694, see references there), when each prime factor occurs to a power > 1. - M. F. Hasler, Feb 12 2008 Also solutions to equation tau_{-2}(n)=0, where tau_{-2} is A007427. - Enrique Pérez Herrero, Jan 19 2013 Numbers whose sum of bi-unitary divisors is greater than the sum of unitary divisors: A188999(n)>A034448(n). - - Paolo P. Lava, Sep 25 2014 LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 Eric Weisstein's World of Mathematics, Cubefree. FORMULA A212793(a(n)) = 0. - Reinhard Zumkeller, May 27 2012 MAPLE isA046099 := proc(n)     local p;     for p in ifactors(n)[2] do         if op(2, p) >= 3 then             return true;         end if;     end do:     false ; end proc: for n from 1 do     if isA046099(n) then         printf("%d\n", n) ;     end if; end do: # R. J. Mathar, Dec 08 2015 MATHEMATICA lst={}; Do[a=0; Do[If[FactorInteger[m][[n, 2]]>2, a=1], {n, Length[FactorInteger[m]]}]; If[a==1, AppendTo[lst, m]], {m, 10^3}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 15 2008 *) PROG (Haskell) a046099 n = a046099_list !! (n-1) a046099_list = filter ((== 1) . a212793) [1..] -- Reinhard Zumkeller, May 27 2012 (PARI) is(n)=n>7 && vecmax(factor(n)[, 2])>2 \\ Charles R Greathouse IV, Sep 17 2015 CROSSREFS Complement of A004709. Subsequences: A000578 and A030078. Cf. A036966, A046101, A001694. Sequence in context: A048108 A228957 A137845 * A033859 A177899 A246311 Adjacent sequences:  A046096 A046097 A046098 * A046100 A046101 A046102 KEYWORD nonn AUTHOR EXTENSIONS More terms from Vladimir Joseph Stephan Orlovsky, Aug 15 2008 Edited by N. J. A. Sloane, Jul 27 2009 STATUS approved

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Last modified October 21 14:52 EDT 2019. Contains 328301 sequences. (Running on oeis4.)