This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A077761 #163 Mar 20 2025 18:40:08 %S A077761 2,6,1,4,9,7,2,1,2,8,4,7,6,4,2,7,8,3,7,5,5,4,2,6,8,3,8,6,0,8,6,9,5,8, %T A077761 5,9,0,5,1,5,6,6,6,4,8,2,6,1,1,9,9,2,0,6,1,9,2,0,6,4,2,1,3,9,2,4,9,2, %U A077761 4,5,1,0,8,9,7,3,6,8,2,0,9,7,1,4,1,4,2,6,3,1,4,3,4,2,4,6,6,5,1,0,5,1,6,1,7 %N A077761 Decimal expansion of Mertens's constant, which is the limit of (Sum_{i=1..k} 1/prime(i)) - log(log(prime(k))) as k goes to infinity, where prime(i) is the i-th prime number. %C A077761 Graham, Knuth & Patashnik incorrectly give this constant as 0.261972128. - _Robert G. Wilson v_, Dec 02 2005 [This was corrected in the second edition (1994). - _T. D. Noe_, Mar 11 2017] %C A077761 Also the average deviation of the number of distinct prime factors: sum_{n < x} omega(n) = x log log x + B_1 x + O(x) where B_1 is this constant, see (e.g.) Hardy & Wright. - _Charles R Greathouse IV_, Mar 05 2021 %C A077761 Named after the Polish mathematician Franz Mertens (1840-1927). Sometimes called Meissel-Mertens constant, after Mertens and the German astronomer Ernst Meissel (1826-1895). - _Amiram Eldar_, Jun 16 2021 %D A077761 Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2004, pp. 94-98 %D A077761 Ronald L. Graham, Donald E. Knuth and Oren Patashnik, Concrete Mathematics, A Foundation For Computer Science, Addison-Wesley, Reading, MA, 1989, p. 23. %D A077761 G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 4th ed. (1975). Oxford, England: Oxford University Press. See 22.10, "The number of prime factors of n". %D A077761 József Sándor, Dragoslav S. Mitrinovic, Borislav Crstici, Handbook of Number Theory I, Springer Science & Business Media, 2005, Section VII.28, p. 257. %H A077761 Eduard Baumann, <a href="/A077761/b077761.txt">Table of n, a(n) for n = 0..9999</a> (first 5001 digits from Robert G. Wilson v), Dec 03 2024. %H A077761 Christian Axler, <a href="http://math.colgate.edu/~integers/s52/s52.Abstract.html">New estimates for some functions defined over primes</a>, Integers, Vol. 18 (2018), Article #A52. %H A077761 Chris Caldwell, The Prime Pages, <a href="https://t5k.org/infinity.shtml#punchline">There are infinitely many primes, but, how big of an infinity?</a> %H A077761 Henri Cohen, <a href="http://www.math.u-bordeaux.fr/~cohen/hardylw.dvi">High precision computation of Hardy-Littlewood constants</a>, preprint, 1998. - From _N. J. A. Sloane_, Jan 26 2013 %H A077761 Pierre Dusart, <a href="https://doi.org/10.1007/s11139-016-9839-4">Explicit estimates of some functions over primes</a>, The Ramanujan Journal, Vol. 45 (2018), pp. 227-251. %H A077761 Pierre Dusart, <a href="https://doi.org/10.37394/23206.2023.22.57">On the divergence of the sum of prime reciprocals</a>, WSEAS Transactions on Math. (2023) Vol.22, 508-513. %H A077761 Steven R. Finch, <a href="https://doi.org/10.1017/9781316997741">Mathematical Constants II</a>, Encyclopedia of Mathematics and Its Applications, Cambridge University Press, Cambridge, 2018, p. 203. %H A077761 Philippe Flajolet and Ilan Vardi, <a href="http://algo.inria.fr/flajolet/Publications/landau.ps">Zeta function expansions of some classical constants</a>. %H A077761 Tengiz O. Gogoberidze, <a href="https://arxiv.org/abs/2407.12047">Baker's dozen digits of two sums involving reciprocal products of an integer and its greatest prime factor</a>, arXiv:2407.12047 [math.GM], 2024. See p. 3. %H A077761 Peter Lindqvist and Jaak Peetre, <a href="https://citeseerx.ist.psu.edu/document?repid=rep1&doi=0ff00f98eb25cbd076cf7a18f85ae51e4b95f618">On the remainder in a series of Mertens</a>, Expos. Math. 15 (1997) 467-478. %H A077761 Peter Lindqvist and Jaak Peetre, <a href="/A077761/a077761.pdf">On a number theoretic sum considered by Meissel : a historical observation</a>, Nieuw Archief voor Wiskunde (Serie 4) 1997 Vol. 15 (3) pp. 175-179. %H A077761 Ernst Meissel, <a href="/A077761/a077761_1.jpg">Bericht über die Provinzial-Gewerbe-Schule zu Iserlohn 1866. Title page</a> [courtesy Archiv der Berlin-Brandenburgischen Akademie der Wissenschaften] %H A077761 Ernst Meissel, <a href="/A077761/a077761.jpg">Bericht über die Provinzial-Gewerbe-Schule zu Iserlohn 1866. Notiz No. 55</a> [courtesy Archiv der Berlin-Brandenburgischen Akademie der Wissenschaften]. %H A077761 Ernst Meissel, <a href="https://doi.org/10.1007/BF01444045">Ueber die Bestimmung der Primzahlenmenge innerhalb gegebener Grenzen</a>, Math. Ann. 2 (4) (1870) 636-642, <a href="https://eudml.org/doc/156468">EuDML</a> %H A077761 Pieter Moree, <a href="https://web.archive.org/web/20050320062638/http://web.inter.nl.net/hcc/J.Moree/linnumb.htm">Mathematical constants</a>. %H A077761 Rikard Olofsson, <a href="https://doi.org/10.1016/j.jnt.2010.06.014">Properties of the Beurling generalized primes</a>, Journal of Number Theory (Volume 131), Issue 1, January 2011, Pages 45-58 (p.51). %H A077761 Dimbinaina Ralaivaosaona and Faratiana Brice Razakarinoro, <a href="https://arxiv.org/abs/2001.05782">An explicit upper bound for Siegel zeros of imaginary quadratic fields</a>, arXiv:2001.05782 [math.NT], 2020. %H A077761 Xavier Gourdon and Pascal Sebah, <a href="http://numbers.computation.free.fr/Constants/constants.html">Constants from number theory</a> %H A077761 Torsten Sillke, <a href="http://www.mathematik.uni-bielefeld.de/~sillke/PUZZLES/harmonic-series">The Harmonic Numbers and Series</a>. %H A077761 Jonathan Sondow and Kieren MacMillan, <a href="http://www.jstor.org/stable/10.4169/amer.math.monthly.124.3.232">Primary pseudoperfect numbers, arithmetic progressions, and the Erdos-Moser equation</a>, Amer. Math. Monthly, Vol. 124, No. 3 (2017), pp. 232-240; also on <a href="http://arxiv.org/abs/1812.06566">arXiv preprint</a>, arXiv:math/1812.06566 [math.NT], 2018. %H A077761 Mark B. Villarino, <a href="https://arxiv.org/abs/math/0504289">Mertens' proof of Mertens' Theorem</a>, arXiv:math/0504289 [math.HO], 2005. %H A077761 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MertensConstant.html">Mertens Constant</a>. %H A077761 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PrimeZetaFunction.html">Prime Zeta Function</a>. %H A077761 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HarmonicSeriesofPrimes.html">Harmonic Series of Primes</a>. %H A077761 Wikipedia, <a href="https://en.wikipedia.org/wiki/Meissel%E2%80%93Mertens_constant">Meissel-Mertens constant</a>. %H A077761 Marek Wójtowicz, <a href="http://dx.doi.org/10.3792/pjaa.87.22">Another proof on the existence of Mertens's constant</a>, Proc. Japan Acad. Ser. A Math. Sci., Vol. 87, No. 2 (2011), pp. 22-23. %F A077761 Equals A001620 - Sum_{n>=2} zeta_prime(n)/n where the zeta prime sequence is A085548, A085541, A085964, A085965, A085966 etc. [Sebah and Gourdon] - _R. J. Mathar_, Apr 29 2006 %F A077761 Equals gamma + Sum_{p prime} (log(1-1/p) + 1/p), where gamma is Euler's constant (A001620). - _Amiram Eldar_, Dec 25 2021 %F A077761 Equals lim_{k->oo} -k + Sum_{p prime} 1/(p*log(p)^(1/k)) conjectured by Meissel in 1866 and proven by Peter Lindqvist and Jaak Peetre in 1997 see links - _Artur Jasinski_, Mar 11 2025 %e A077761 0.26149721284764278375542683860869585905156664826119920619206421392... %t A077761 $MaxExtraPrecision = 400; RealDigits[ N[EulerGamma + NSum[(MoebiusMu[m]/m)*Log[N[Zeta[m], 120]], {m, 2, 1000}, Method -> "EulerMaclaurin", AccuracyGoal -> 120, NSumTerms -> 1000, PrecisionGoal -> 120, WorkingPrecision -> 120] , 120]][[1, 1 ;; 105]] %t A077761 (* or, from version 7 up: *) digits = 105; M = EulerGamma - NSum[ PrimeZetaP[n] / n, {n, 2, Infinity}, WorkingPrecision -> digits+10, NSumTerms -> 3*digits]; RealDigits[M, 10, digits] // First (* _Jean-François Alcover_, Mar 16 2011, updated Sep 01 2015 *) %Y A077761 Cf. A001620. %K A077761 cons,nonn %O A077761 0,1 %A A077761 _T. D. Noe_, Nov 14 2002