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%I #20 May 05 2024 01:51:17
%S 1,7,29,129,571,2525,11167,49372,218295,965177,4267457,18868240,
%T 83424514,368855252,1630865929,7210751807,31881800153
%N Least number m such that the Sigma-Harmonic sequence Sum_{k=1..m} 1/sigma(k) >= n.
%D Jean-Marie De Koninck, Ces nombres qui nous fascinent, Entry 129, p. 44, Ellipses, Paris, 2008.
%F Limit_{n->oo} a(n+1)/a(n) = exp(1/c) = 4.42142525588146107878... where c = A308039. - _Amiram Eldar_, May 05 2024
%t {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}]
%Y Cf. A000203 (sigma), A002387, A004080, A046024, A074631, A074633, A074467, A212717, A308039.
%K nonn,more
%O 1,2
%A _Labos Elemer_, Aug 29 2002
%E 2 more terms from _Lekraj Beedassy_, Jul 14 2008
%E a(11)-a(15) from _Donovan Johnson_, Aug 22 2011
%E a(16)-a(17) from _Amiram Eldar_, May 05 2024
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