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 A064016 a(n) = sum_{k <= 10^n} cototient(k), where cototient is A051953. 0
 0, 23, 2006, 196308, 19607514, 1960399246, 196036947608, 19603648572758, 1960364533634092, 196036449326991586, 19603644912113783634, 1960364490766613788860, 196036449073440195974090 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Conjecture: It would appear that the sum from 1 to n approaches the limit 0.1960364...*n^2 = (1/2 - 3/Pi^2)*n^2. LINKS MATHEMATICA s = 0; k = 1; Do[ While[ k <= 10^n, s = s + k - EulerPhi[ k ]; k++ ]; Print[ s ], {n, 0, 8} ] CROSSREFS Cf. A002088, A051953, A063986. Sequence in context: A319508 A269122 A132395 * A263462 A138735 A220653 Adjacent sequences:  A064013 A064014 A064015 * A064017 A064018 A064019 KEYWORD nonn AUTHOR Robert G. Wilson v, Sep 07 2001 EXTENSIONS a(9) from Jud McCranie, Jun 25 2005 a(10)-a(11) from Donovan Johnson, Feb 06 2010 a(12) from Donovan Johnson, Feb 07 2012 STATUS approved

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Last modified September 20 05:51 EDT 2019. Contains 327212 sequences. (Running on oeis4.)