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A357700
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Noncubefree numbers k such that A073185(k) > 2*k.
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1
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360360, 471240, 1801800, 2356200, 2522520, 2633400, 2784600, 3112200, 3187800, 3298680, 3686760, 3767400, 3898440, 3963960, 4019400, 4296600, 4462920, 4684680, 5128200, 5183640, 5682600, 5793480, 6126120, 6846840, 8011080, 8288280, 8953560, 10210200, 10450440
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OFFSET
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1,1
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COMMENTS
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The cubefree numbers k such that A073185(k) > 2*k are the cubefree abundant numbers (A357695).
The least odd term is (3/4) * prime(13)# * prime(197)# = 6.252...*10^517.
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LINKS
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EXAMPLE
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360360 = 2^3 * 45045 is a term since it is divisible by a cube and A073185(360360) = 733824 > 2*360360.
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MATHEMATICA
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f[p_, e_] := 1 + p + If[e == 1, 0, p^2]; q[n_] := AnyTrue[(fct = FactorInteger[n])[[;; , 2]], # > 2 &] && Times @@ f @@@ fct > 2*n; Select[Range[2, 5*10^6], q]
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PROG
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(PARI) is(n) = {my(f = factor(n)); if(n == 1 || vecmax(f[, 2]) < 3, return(0)); prod(i=1, #f~, 1 + f[i, 1] + if(f[i, 2]==1, 0, f[i, 1]^2)) > 2*n};
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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