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A086974
Numbers of the form p^2 * q * r with distinct primes p, q and r such that p^2 < q*r.
3
60, 84, 90, 126, 132, 140, 156, 198, 204, 220, 228, 234, 260, 276, 306, 308, 315, 340, 342, 348, 364, 372, 380, 414, 444, 460, 476, 492, 495, 516, 522, 532, 558, 564, 572, 580, 585, 620, 636, 644, 650, 666, 693, 708, 732, 738, 740, 748, 765, 774, 804
OFFSET
1,1
LINKS
FORMULA
A002033(a(n)-1) = 44. - Juri-Stepan Gerasimov, Sep 26 2009
MATHEMATICA
q[n_] := Module[{f = SortBy[FactorInteger[n], Last]}, f[[;; , 2]] == {1, 1, 2} && f[[1, 1]] * f[[2, 1]] > f[[3, 1]]^2]; Select[Range[1000], q] (* Amiram Eldar, Sep 15 2024 *)
CROSSREFS
Sequence in context: A174292 A085987 A356413 * A099831 A306222 A138604
KEYWORD
nonn,easy
AUTHOR
Reinhard Zumkeller, Jul 25 2003
EXTENSIONS
Incorrect comment removed by Charles R Greathouse IV, Mar 22 2010
STATUS
approved