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%I #11 Apr 25 2017 18:58:47
%S 27,37,54,74,108,111,135,148,185,216,222,270,296,333,370,432,444,540,
%T 555,592,666,675,740,864,888,925,999,1080,1110,1184,1332,1350,1480,
%U 1665,1728,1776,1850,1998,2160,2220,2368,2664,2700,2775,2960,3330,3375,3456,3552,3700,3996,4320,4440,4625,4736,4995
%N 1/n has period 3 in base 10.
%H Ray Chandler, <a href="/A069105/b069105.txt">Table of n, a(n) for n = 1..348</a>
%F Numbers of the form a*b*c where a is in {27, 37, 111, 333, 999}, b is a power of 2 and c is a power of 5. - _Henry Bottomley_, Apr 12 2002
%F Equivalently: A132740(n) divides 999 but does not divide 9. - _M. F. Hasler_, Apr 25 2017
%e 1/1332 = 0.000750750750...
%t Select[ Range[7500], Length[ RealDigits[1/# ] [[1, -1]]] == 3 &]
%o (PARI) is(n,S=[27,37,111,333,999])=setsearch(S,n\5^valuation(n,5)>>valuation(n,2)) \\ _M. F. Hasler_, Apr 25 2017
%Y Cf. A018766, A003592, A070021, A070022, A070023.
%K base,easy,nonn
%O 1,1
%A Joshua Horowitz (mccartneyman(AT)yahoo.com), Apr 07 2002
%E Extended by _Robert G. Wilson v_, Apr 07 2002
%E Terms added and program corrected to agree with description by _Ray Chandler_, Apr 17 2017
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