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A195212
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Numbers n for which the exponent of the largest prime factor of n is even.
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2
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4, 9, 16, 18, 25, 36, 49, 50, 64, 72, 75, 81, 98, 100, 121, 144, 147, 150, 162, 169, 196, 200, 225, 242, 245, 256, 288, 289, 294, 300, 324, 338, 361, 363, 392, 400, 441, 450, 484, 490, 507, 529, 576, 578, 588, 600, 605, 625, 648, 675, 676, 722, 726, 729, 735
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OFFSET
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1,1
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COMMENTS
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What is the density of these numbers? It's clear that lim a(n)/n^2 = 0.
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LINKS
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MATHEMATICA
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Select[Range[800], EvenQ[FactorInteger[#][[-1, 2]]]&] (* Harvey P. Dale, Jul 22 2013 *)
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PROG
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CROSSREFS
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Contains the squares, A000290, as a subsequence (apart from 0 and 1).
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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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