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%I #18 May 26 2023 05:43:13
%S 1,8,3,9,3,9,9,0,8,4,0,4,5,0,4,7,0,6,6,2,4,7,3,0,5,4,7,9,5,6,7,2,3,0,
%T 4,7,6,4,2,2,7,8,3,5,9,4,8,1,7,7,3,0,5,7,9,1,6,7,9,7,8,6,7,7,5,7,2,8,
%U 1,8,2,5,2,6,4,3,7,3,3,5,2,2,8,4,1,5,8,7,4,1,3,3,9,6,6,0,3,7,7,6,0,2,9,3,6
%N Decimal expansion of 4th Madelung constant (negated).
%D Steven R. Finch, Mathematical Constants, Cambridge, 2003, p. 77.
%F M_4 = -8*(5-3*sqrt(2))*zeta(1/2)*zeta(-1/2).
%e -1.83939908404504706624730547956723047642278359481773...
%t RealDigits[8*(5 - 3*Sqrt[2])*Zeta[1/2]*Zeta[-1/2], 10, 120][[1]] (* _Amiram Eldar_, May 26 2023 *)
%o (PARI) 8*(5-3*sqrt(2))*zeta(1/2)*zeta(-1/2) \\ _Charles R Greathouse IV_, Jun 07 2016
%Y Cf. A059750, A088537, A085469.
%K cons,nonn
%O 1,2
%A _Benoit Cloitre_, Jan 18 2004