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A074470
Subscript m such that PhiComposite-Harmonic series cd[m]=Sum[1/A000010[A002808(k)],{k,1,m}]>=n.
1
2, 7, 16, 31, 60, 113, 205, 371, 663, 1176, 2069, 3631, 6341, 11039, 19159, 33164, 57287, 98763, 169967, 292061, 501165, 858892, 1470334, 2514423, 4295912, 7333264, 12508213, 21319360, 36312685, 61811287, 105152840, 178787270, 303829041, 516074615, 876190239
OFFSET
1,1
MATHEMATICA
c[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] {s=0, s1=0}; Do[s=s+(1/EulerPhi[c[n]]); If[Greater[Floor[s], s1], s1=Floor[s]; Print[{n, Floor[s]}]], {n, 1, 1000000}]
KEYWORD
hard,nonn
AUTHOR
Labos Elemer, Sep 05 2002
EXTENSIONS
More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Jul 23 2005
a(30)-a(35) from Donovan Johnson, Aug 21 2011
STATUS
approved