

A105115


Numbers k such that the decimal representation of 1/k is neither terminating nor purely repeating.


7



6, 12, 14, 15, 18, 22, 24, 26, 28, 30, 34, 35, 36, 38, 42, 44, 45, 46, 48, 52, 54, 55, 56, 58, 60, 62, 65, 66, 68, 70, 72, 74, 75, 76, 78, 82, 84, 85, 86, 88, 90, 92, 94, 95, 96, 98, 102, 104, 105, 106, 108, 110, 112, 114, 115, 116, 118, 120, 122, 124, 126, 130, 132, 134
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OFFSET

1,1


COMMENTS

k is in this sequence iff 1) k is divisible by 2 or 5 and 2) k is also divisible by some prime other than 2 and 5. Contains the numbers that are in neither A003592 nor A045572.
The asymptotic density of this sequence is 3/5.  Amiram Eldar, Mar 26 2021


LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000


EXAMPLE

22 is a member because 1/22 = .045454545..., which has a 0 before the repeating 45.


MATHEMATICA

f[n_, lim_] := Block[{g, a}, g[x_] := First /@ FactorInteger@ x; a = g@ n; Select[Range@ lim, And[1 < GCD[#, n] < #, Length@ Complement[g@ #, a] >= 1] &]]; f[10, 134] (* Michael De Vlieger, Jun 20 2015 *)


CROSSREFS

Cf. A003592, A045572.
Sequence in context: A348551 A143957 A318981 * A325700 A306999 A246048
Adjacent sequences: A105112 A105113 A105114 * A105116 A105117 A105118


KEYWORD

base,easy,nonn


AUTHOR

David Wasserman, Apr 07 2005


STATUS

approved



