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%I #11 Oct 15 2013 22:31:29
%S 32,301,2123,13172,76105,420007,2245009,11719362,60071831,303487314,
%T 1515211979
%N Subscript m such that SigmaComposite-Harmonic series cd[m]=Sum[1/A000203[A002808(k)],{k,1,m}]>=n.
%t c[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] {s=0, s1=0}; Do[s=s+(1/DivisorSigma[1, c[n]]); If[Greater[Floor[s], s1], s1=Floor[s]; Print[{n, Floor[s]}]], {n, 1, 1000000}]
%o (PARI) a(n)=my(m,s=0.);for(c=4,(2*n+2)^(n+2),if(isprime(c),next,m++);s+=1/sigma(c);if(s>=n,return(m))) \\ _Charles R Greathouse IV_, Feb 19 2013
%Y Cf. A004080, A002387, A002808, A000203, A073255, A046024, A074631, A074633, A074468, A074470.
%K hard,more,nonn
%O 1,1
%A _Labos Elemer_, Sep 05 2002
%E a(6)-a(11) from _Donovan Johnson_, Aug 22 2011
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