A074468 Subscript m such that Sigma-Harmonic sequence, ssi[m]=Sum[1/sigma[k],{k,1,m}] >= n.

1, 7, 29, 129, 571, 2525, 11167, 49372, 218295, 965177, 4267457, 18868240, 83424514, 368855252, 1630865929

Offset

1,2

References

J.-M. De Koninck, Ces nombres qui nous fascinent, Entry 129, p. 44, Ellipses, Paris 2008.

Links

Table of n, a(n) for n=1..15.

Mathematica

{s=0, s1=0}; Do[s=s+(1/DivisorSigma[1, n]); If[Greater[Floor[s], s1], s1=Floor[s]; Print[{n, Floor[s]}]], {n, 1, 1000000}]

Crossrefs

Cf. A002387, A004080, A046024, A074631, A074633, A074467.

Sequence in context: A048876 A126394 A252832 * A303091 A333887 A179599

Adjacent sequences: A074465 A074466 A074467 * A074469 A074470 A074471

Keyword

more,nonn

Author

Labos Elemer, Aug 29 2002

Extensions

2 more terms from Lekraj Beedassy, Jul 14 2008

a(11)-a(15) from Donovan Johnson, Aug 22 2011

Status

approved