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%I #15 Jul 23 2012 13:31:57
%S 5,2,5,41,3,2,2,2,17,13,11,89,7,5,5,5,41,3,3,347,3,3,3,29,2,2,2,2,
%T 26041,2,2,2,23,2,2,2,2,2,17,13,13,1201,11,11,107,919,89,7,7,7,7,7,7,
%U 61,5,5,5,5,5,5,5,5,5,5,5,5,41,4111,3
%N Prime preperiodic part of the decimal expansion of 1/k as k runs through A065502.
%C Primes in A175555 in the order of appearance.
%C Multiples of 2 or 5 generate a quotient with a preperiodic sequence of digits, for example 1/24 = 0.041666666..., and 41 is the decimal form of the preperiodic part.
%C The corresponding values of n are: 2, 5, 20, 24, 28, 36, 44, 50, 56, 72, 88, 112, 136, 168, 184, ...
%D H. Rademacher and O. Toeplitz, Von Zahlen und Figuren (Springer 1930, reprinted 1968), ch. 19, 'Die periodischen Dezimalbrueche'.
%e The prime 347 is in the sequence because 1/288 = .00347222222222222222...
%e The prime 1201 is in the sequence because 1/832 =.001201 923076 923076 ...
%p for n from 1 do
%p p := A175555(n) ;
%p if isprime(p) then
%p print(p) ;
%p end if;
%p end do: # _R. J. Mathar_, Jul 22 2012
%Y Cf. A175555, A036275, A065502.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Jun 30 2010
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