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 A272030 #35 Apr 28 2018 04:06:33
%S A272030 3,1,7,0,4,5,9,3,4,2,1,4,2,5,6,6,3,6,5,3,2,6,4,8,8,2,4,8,8,8,2,2,6,3,
%T A272030 0,2,8,5,6,1,2,5,4,4,3,6,3,1,7,9,8,9,4,8,7,4,2,1,4,3,3,9,8,0,7,2,2,8,
%U A272030 7,1,4,3,3,5,7,3,8,2,4,8,1,4,0,7,7,0,3,4,6,4,2,7,8,6,0,7,7,0
%N A272030 Decimal expansion of C = log(2*Pi) + B_3 (where B_3 is A083343), one of Euler totient constants.
%D A272030 Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.7 Euler totient constants, p. 117.
%F A272030 C = log(2*Pi) + EulerGamma - Sum_{n >= 2} P'(n), where P'(n) is the prime zeta P function derivative.
%e A272030 3.17045934214256636532648824888226302856125443631798948742143398...
%t A272030 digits = 98; B3 = EulerGamma - NSum[PrimeZetaP'[n], {n, 2, Infinity}, WorkingPrecision -> 2 digits, NSumTerms -> 200]; RealDigits[Log[2 Pi] + B3, 10, digits][[1]]
%Y A272030 Cf. A001620, A005596, A065484, A065485, A080130, A082695, A082695, A083343.
%K A272030 nonn,cons
%O A272030 1,1
%A A272030 _Jean-François Alcover_, Apr 25 2016