|
%I #20 Jan 25 2024 02:41:56
%S 1,0,6,3,8,7,2,4,2,8,2,4,4,5,4,6,6,0,0,1,6,0,7,3,4,3,6,3,7,0,2,1,4,0,
%T 2,0,8,4,9,5,7,6,7,1,3,4,0,5,8,5,8,8,7,6,2,8,7,8,8,9,4,8,3,4,8,8,8,8,
%U 1,7,7,7,0,1,0,3,4,7,2,1,3,2,5,0,7,6,9,7,3,7,6,2,1,9,0,2,9,2,9,4,9,4
%N Decimal expansion of 21/(2*Pi^2).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MoebiusFunction.html">Moebius Function</a>.
%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>.
%F Equals Sum_{k>=1} 1/A030229(k)^2. - _Amiram Eldar_, May 23 2020
%F Equals zeta(4)/zeta(6). - _Terry D. Grant_, Nov 07 2020
%F Equals Sum_{k>=1} A007434(k)/k^6. - _Amiram Eldar_, Jan 25 2024
%e 1.06387242824454660016073436370214020849576713405858...
%t RealDigits[21/2/Pi^2, 10, 100][[1]] (* _Amiram Eldar_, May 23 2020 *)
%o (PARI) 21/2/Pi^2 \\ _Charles R Greathouse IV_, Oct 01 2022
%Y Cf. A007434, A030229, A082020, A088245.
%Y Cf. A104141.
%K nonn,cons
%O 1,3
%A _Eric W. Weisstein_, Sep 25 2003
|
