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 A072587 Numbers having at least one prime factor with an even exponent. 11
 4, 9, 12, 16, 18, 20, 25, 28, 36, 44, 45, 48, 49, 50, 52, 60, 63, 64, 68, 72, 75, 76, 80, 81, 84, 90, 92, 98, 99, 100, 108, 112, 116, 117, 121, 124, 126, 132, 140, 144, 147, 148, 150, 153, 156, 162, 164, 169, 171, 172, 175, 176, 180, 188, 192, 196, 198, 200, 204 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Complement of the union of {1} and A002035. [Correction, Nov 15 2012] A162645 is a subsequence and this sequence is a subsequence of A162643. - Reinhard Zumkeller, Jul 08 2009 Numbers whose sum of divisors is greater than the sum of bi-unitary divisors: A000203(a(n)) > A188999(a(n)). - Paolo P. Lava, Oct 08 2014 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 MATHEMATICA Select[Range[210], MemberQ[EvenQ[Transpose[FactorInteger[#]][[2]]], True] &] (* Harvey P. Dale, Apr 03 2012 *) PROG (Haskell) a072587 n = a072587_list !! (n-1) a072587_list = tail \$ filter (any even . a124010_row) [1..] -- Reinhard Zumkeller, Nov 15 2012 (PARI) is(n)=n>3 && Set(factor(n)[, 2]%2)[1]==0 \\ Charles R Greathouse IV, Oct 16 2015 CROSSREFS Cf. A000037, A072588, A124010. Sequence in context: A066423 A072498 A162643 * A240112 A162645 A135572 Adjacent sequences:  A072584 A072585 A072586 * A072588 A072589 A072590 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jun 23 2002 EXTENSIONS Thanks to Zak Seidov who noticed that 1 had to be removed. - Reinhard Zumkeller, Nov 15 2012 STATUS approved

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Last modified October 15 10:15 EDT 2019. Contains 328026 sequences. (Running on oeis4.)