OFFSET
1,1
COMMENTS
If 1/n = 0.XYYYYY... then sequence gives index of first digit of the second Y.
a(4) = 4 and a(p) = p for primes p = {7, 17, 19, 23, 29, 47, 59, 61, 97, ...} = A001913(n) Cyclic numbers: primes with primitive root 10. - Alexander Adamchuk, Jan 28 2007
FORMULA
EXAMPLE
a(4) = 4 because in 0.2500 the zero begins repeating at the fourth position.
a(17) = 17 because 0.05882352941176470588... begins repeating at the 17th position.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Ben Paul Thurston, Sep 14 2006
STATUS
approved