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%I #6 Nov 21 2013 12:47:47
%S 11,22,33,44,55,66,88,99,110,132,165,176,198,220,264,275,330,352,396,
%T 440,495,528,550,660,704,792,825,880,990,1056,1100,1320,1375,1408,
%U 1584,1650,1760,1980,2112,2200,2475,2640,2750,2816,3168,3300,3520,3960,4125
%N 1/n has period 2 in base 10.
%F a(n) =11*A070023(n). Numbers of the form a*b*c where a is in {11, 33, 99}, b is a power of 2 and c is a power of 5.
%e 176 is in the sequence since 1/176=0.00568181818181818...
%t Select[Range[5000],Length[RealDigits[1/#][[1,-1]]]==2&] (* _Harvey P. Dale_, Oct 10 2011 *)
%Y Cf. A018282, A003592, A069105, A070021, A070023.
%K base,nonn
%O 1,1
%A _Henry Bottomley_, Apr 12 2002