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 A058210 Floor( exp(gamma) n log log n ), where gamma is Euler's constant (A001620). 5
 -2, 0, 2, 4, 6, 8, 10, 12, 14, 17, 19, 21, 24, 26, 29, 31, 34, 36, 39, 41, 44, 46, 49, 52, 54, 57, 60, 62, 65, 68, 70, 73, 76, 79, 81, 84, 87, 90, 92, 95, 98, 101, 104, 107, 109, 112, 115, 118, 121, 124, 127, 130, 133, 135, 138, 141, 144, 147, 150 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS Theorem (G. Robin): exp(gamma) n log log n > sigma(n) for all n >= 5041 if and only if the Riemann Hypothesis is true. Note that a(n) <= exp(gamma) n log log n < a(n) + 1. REFERENCES D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section III.2.2.b. G. Robin, Grandes valeurs de la fonction somme des diviseurs et hypothese de Riemann, J. Math. Pures Appl. 63 (1984), 187-213. LINKS G. C. Greubel, Table of n, a(n) for n = 2..1000 G. Caveney, J.-L. Nicolas, and J. Sondow, Robin's theorem, primes, and a new elementary reformulation of the Riemann Hypothesis, Integers 11 (2011), #A33. G. Caveney, J.-L. Nicolas and J. Sondow, On SA, CA, and GA numbers, Ramanujan J., 29 (2012), 359-384. MATHEMATICA Table[Floor[Exp[EulerGamma]*n*Log[Log[n]]], {n, 2, 50}] (* G. C. Greubel, Dec 31 2016 *) CROSSREFS See A058209. Sequence in context: A194739 A194765 A239229 * A274414 A079550 A226430 Adjacent sequences:  A058207 A058208 A058209 * A058211 A058212 A058213 KEYWORD sign AUTHOR N. J. A. Sloane, Nov 30 2000 EXTENSIONS Statement of Robin's theorem corrected by Jonathan Sondow, May 30 2011 STATUS approved

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