OFFSET
1,5
COMMENTS
a[n] = 0 precisely when n is a power of 2.
MATHEMATICA
Table[If[n == 1, 0, (fl = FactorInteger[n]; pq = Table[1, {i, 1, PrimePi[Last[fl][[1]]]}]; While[Length[fl] > 0, pp = First[fl]; fl = Drop[fl, 1]; pq[[PrimePi[pp[[1]]]]] = pp[[2]] + 1; ]; Mod[Numerator[FromContinuedFraction[pq]], Denominator[FromContinuedFraction[pq]]])], {n, 1, 80}]
CROSSREFS
KEYWORD
frac,hard,nonn
AUTHOR
Joseph Biberstine (jrbibers(AT)indiana.edu), Jun 12 2006
STATUS
approved