

A061564


Numbers k such that the repeating part of the decimal expansion of 1/k (omitting leading or trailing zeros) forms a prime number.


1



3, 12, 18, 27, 30, 33, 36, 45, 48, 75, 120, 180, 192, 198, 270, 288, 300, 330, 333, 360, 369, 450, 480, 495, 750, 768, 909, 1152, 1200, 1584, 1800, 1875, 1920, 1980, 1998, 2151, 2304, 2439, 2700, 2880, 2997, 3000, 3072, 3300, 3330, 3333, 3600, 3690, 4500, 4800
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OFFSET

1,1


LINKS



EXAMPLE

1/18 = 0.05555555..., the repeating part is 5, so 18 is in the sequence.
277 is not a term because the repetend of 1/277 is 3610108303249097472924187725631768953068592057761732851985559566787, which is not a prime.  Barry Smyth, Mar 31 2022


CROSSREFS



KEYWORD

easy,nonn,base


AUTHOR

Brian Wallace (wallacebrianedward(AT)yahoo.co.uk), May 18 2001


EXTENSIONS



STATUS

approved



