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A120251
A120249[n] modulo A120250[n].
2
0, 0, 1, 0, 2, 1, 3, 0, 1, 2, 5, 1, 8, 3, 2, 0, 13, 1, 21, 2, 3, 5, 34, 1, 3, 8, 1, 3, 55, 2, 89, 0, 5, 13, 5, 1, 144, 21, 8, 2, 233, 3, 377, 5, 2, 34, 610, 1, 4, 3, 13, 8, 987, 1, 8, 3, 21, 55, 1597, 2, 2584, 89, 3, 0, 13, 5, 4181, 13, 34, 5, 6765, 1, 10946, 144, 3, 21, 7, 8, 17711, 2
OFFSET
1,5
COMMENTS
a[n] = 0 precisely when n is a power of 2.
FORMULA
a[n] = Mod[A120249[n], A120250[n]]
EXAMPLE
a[n] = A120249[2646] modulo A120250[2646] = 42 modulo 19 = 4
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
Cf. Corresponding denominators in A120250.
Sequence in context: A328167 A253556 A252735 * A333429 A071490 A194893
KEYWORD
frac,hard,nonn
AUTHOR
Joseph Biberstine (jrbibers(AT)indiana.edu), Jun 12 2006
STATUS
approved