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A162828
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Positive numbers n such that 2*90*n/(90+n) are integers.
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1
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10, 18, 30, 45, 60, 72, 90, 110, 126, 135, 180, 210, 234, 270, 315, 360, 450, 510, 558, 585, 720, 810, 990, 1260, 1530, 1710, 1935, 2610, 3150, 3960, 5310, 8010, 16110
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listen;
history;
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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f[a_, b_]:=(a*b)/(a+b)*2; a=90; lst={}; Do[If[f[a, n]==IntegerPart[f[a, n]], AppendTo[lst, n]], {n, 9!}]; lst
Select[Range[17000], IntegerQ[180 #/(#+90)]&] (* Harvey P. Dale, Sep 22 2011 *)
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CROSSREFS
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Cf. A162688, A162689, A162690, A162691, A162692, A162693, A162694, A162817, A162818, A162819, A162820, A162821, A162822, A162823, A162824, A162825, A162826
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KEYWORD
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nonn,fini,full
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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