# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a229523 Showing 1-1 of 1 %I A229523 #43 Oct 06 2023 10:53:38 %S A229523 0,38,3906,386517,38671110,3865941752,386580463478,38657862140521, %T A229523 3865783461518530,386578337105347684,38657833484501788407, %U A229523 3865783345588492717623,386578334529872234861944,38657833452536035472588254,3865783345249467526546175599 %N A229523 Partial sum of the arithmetic derivative A003415 (A190121) up to 10^n. %H A229523 Hiroaki Yamanouchi, Table of n, a(n) for n = 0..17 %H A229523 E. J. Barbeau, Remark on an arithmetic derivative, Canad. Math. Bull., Vol. 4, No. 2 (May 1961), pp. 117-122. %F A229523 a(n) = A190121(10^n). %F A229523 It seems that a(n)/10^(2n-1) -> 3.865783... as n -> oo. %F A229523 Note: A190121 ~ 0.374... * n^2 [Barbeau]. - _Giorgio Balzarotti_, Oct 15 2013 %F A229523 a(n) ~ 0.386578334524897563932183729927 * 100^n. - _Hiroaki Yamanouchi_, Jul 09 2014 %F A229523 The constant is (1/2) * Sum_{p prime} 1/(p*(p-1)) = A136141 / 2 = 0.3865783345... . This constant was given by Barbeau (1961) but with the wrong value 0.374. - _Amiram Eldar_, Oct 06 2023 %o A229523 (PARI) s=0;for(k=0,8,for(n=10^(k-1)+1,10^k,s+=A003415(n));print1(s","));s %Y A229523 Cf. A003415, A136141, A190121. %K A229523 nonn,hard %O A229523 0,2 %A A229523 _M. F. Hasler_, Sep 25 2013 %E A229523 a(8)-a(10) from _Donovan Johnson_, Sep 25 2013 %E A229523 a(11)-a(12) from _Giovanni Resta_, Mar 13 2014 %E A229523 a(13)-a(14) from _Hiroaki Yamanouchi_, Jul 09 2014 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE