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%I #27 Feb 25 2023 05:20:09
%S 3,12,18,27,30,33,36,45,48,75,120,180,192,198,270,288,300,330,333,360,
%T 369,450,480,495,750,768,909,1152,1200,1584,1800,1875,1920,1980,1998,
%U 2151,2304,2439,2700,2880,2997,3000,3072,3300,3330,3333,3600,3690,4500,4800
%N Numbers k such that the repeating part of the decimal expansion of 1/k (omitting leading or trailing zeros) forms a prime number.
%H <a href="/index/1#1overn">Index entries for sequences related to decimal expansion of 1/n</a>
%e 1/18 = 0.05555555..., the repeating part is 5, so 18 is in the sequence.
%e 277 is not a term because the repetend of 1/277 is 3610108303249097472924187725631768953068592057761732851985559566787, which is not a prime. - _Barry Smyth_, Mar 31 2022
%Y Cf. A036275, A060284.
%K easy,nonn,base
%O 1,1
%A Brian Wallace (wallacebrianedward(AT)yahoo.co.uk), May 18 2001
%E Corrected and extended by _Klaus Brockhaus_, May 19 2001
%E More terms from _Lior Manor_, Nov 26 2001
%E Incorrect term 277 removed by _Barry Smyth_, Mar 31 2022
%E Corrected and extended by _Sean A. Irvine_, Feb 25 2023