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 A384949 #40 Jul 28 2025 08:58:26
%S A384949 1,0,0,0,0,5,1,3,4,5,1,8,3,8,4,3,7,7,2,5,9,2,8,1,7,9,0,0,5,4,2,5,0,5,
%T A384949 0,0,5,6,7,9,9,6,9,9,0,2,4,6,6,3,8,3,1,1,4,4,4,5,9,6,2,6,3,8,1,4,4,3,
%U A384949 3,6,2,5,4,4,5,7,8,5,5,5,5,0,5,1,4,9,4,3,0,8,2,6,6,4,0,3,0,5,8,3
%N A384949 Decimal expansion of Sum_{k>=0} 1/(2*k+1)^9.
%H A384949 Jason Bard, <a href="/A384949/b384949.txt">Table of n, a(n) for n = 1..10000</a>
%H A384949 Michael I. Shamos, <a href="http://euro.ecom.cmu.edu/people/faculty/mshamos/cat.pdf">A catalog of the real numbers</a>, (2007). See p. 21.
%F A384949 Equals 511*Zeta(9)/512 = 511/512 * A013667.
%F A384949 Equals Sum_{n>=0} 1/A016761(n). - _Amiram Eldar_, Jul 28 2025
%e A384949 1.00005134518384377259281790054250500567996990246638...
%p A384949 evalf(sum(1/(2*k+1)^9, k=0..infinity), 120); # _Alois P. Heinz_, Jul 26 2025
%t A384949 RealDigits[511*Zeta[9]/512, 10, 100][[1]]
%o A384949 (PARI) 511*zeta(9)/512 \\ _Amiram Eldar_, Jul 28 2025
%Y A384949 Cf. A013667, A016761.
%K A384949 nonn,cons
%O A384949 1,6
%A A384949 _Jason Bard_, Jul 24 2025