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Reciprocal of n terminates with an infinite repetition of digit 2. Multiples of 10 are omitted.
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%I #19 May 03 2021 18:39:35

%S 45,288,18432,703125,1179648,75497472,4831838208,10986328125,

%T 309237645312,19791209299968,171661376953125,1266637395197952,

%U 81064793292668928,2682209014892578125,5188146770730811392

%N Reciprocal of n terminates with an infinite repetition of digit 2. Multiples of 10 are omitted.

%D A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 73-82.

%H Robert Israel, <a href="/A064561/b064561.txt">Table of n, a(n) for n = 1..787</a>

%H <a href="/index/1#1overn">Index entries for sequences related to decimal expansion of 1/n</a>

%F Numbers of the form 9*2^(6i-1) and 9*5^(6i-5) [i>0].

%e 1/1179648 = 0.000000847710503472222222222...

%p sort([seq(9*2^(6*i-1), i=1 .. floor((1+log[2](10^20/9))/6)),

%p seq(9*5^(6*i-5), i=1 .. floor((5+log[5](10^20/9))/6))]); # _Robert Israel_, May 03 2021

%o (ARIBAS): a064560(1,300000000,2,36). For definition of a064560 see A064560.

%Y Cf. A064560, A064562, A064563, A064564, A064565, A064566, A064567.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Sep 20 2001

%E One more term from _Klaus Brockhaus_, Sep 22 2001

%E More terms from _James A. Sellers_, Sep 28 2001