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A088246
Decimal expansion of 21/(2*Pi^2).
4
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, 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, 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
OFFSET
1,3
FORMULA
Equals Sum_{k>=1} 1/A030229(k)^2. - Amiram Eldar, May 23 2020
Equals zeta(4)/zeta(6). - Terry D. Grant, Nov 07 2020
Equals Sum_{k>=1} A007434(k)/k^6. - Amiram Eldar, Jan 25 2024
EXAMPLE
1.06387242824454660016073436370214020849576713405858...
MATHEMATICA
RealDigits[21/2/Pi^2, 10, 100][[1]] (* Amiram Eldar, May 23 2020 *)
PROG
(PARI) 21/2/Pi^2 \\ Charles R Greathouse IV, Oct 01 2022
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Eric W. Weisstein, Sep 25 2003
STATUS
approved