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%I #2 Mar 30 2012 17:35:24
%S 72,120,144,180,240,252,288,336,360,378,400,420,432,450,480,504,540,
%T 576,594,600,630,648,660,672,700,720,756,780,792,800,840,858,864,900,
%U 924,936,960,1008,1050,1056,1080,1092,1120,1152,1170,1188,1200,1225,1248
%N Numbers with two or more distinct factorizations m*k such that m <= k <= 2*m.
%C Numbers n such that A067742(n) >= 3.
%C The smallest number with 3 such factorizations is 840 = 28*30 = 24*35 = 21*40.
%e 72 = 8 * 9 = 6 * 12, so it is in the sequence. 60 = 6 * 10, but the next closest factorization is 5 * 12 and 12 > 2*5, so 60 is not in the sequence.
%Y Cf. A067742, A071562, A100345.
%K nonn
%O 1,1
%A _Franklin T. Adams-Watters_, Apr 04 2010
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