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A258987
Decimal expansion of the multiple zeta value (Euler sum) zetamult(3,3).
12
2, 1, 3, 7, 9, 8, 8, 6, 8, 2, 2, 4, 5, 9, 2, 5, 4, 7, 0, 9, 9, 5, 8, 3, 5, 7, 4, 5, 0, 8, 0, 3, 3, 6, 4, 9, 6, 4, 0, 9, 5, 8, 9, 5, 7, 8, 6, 5, 5, 1, 7, 5, 5, 6, 1, 4, 4, 5, 1, 2, 7, 4, 8, 9, 4, 7, 1, 2, 5, 8, 3, 6, 6, 1, 4, 6, 9, 8, 1, 0, 2, 0, 4, 1, 7, 0, 9, 5, 6, 0, 2, 8, 9, 9, 9, 1, 1, 5, 5, 0, 6, 4, 8
OFFSET
0,1
FORMULA
zetamult(3,3) = Sum_{m>=2} (Sum_{n=1..m-1} 1/(m^3*n^3)) = (1/2)*zeta(3)^2 - (1/2)*zeta(6). - [Corrected by Detlef Meya, Jun 06 2025 ]
EXAMPLE
0.213798868224592547099583574508033649640958957865517556144512748947...
MATHEMATICA
RealDigits[(1/2)*Zeta[3]^2 - (1/2)*Zeta[6], 10, 103] // First (* Corrected by Detlef Meya, Jun 06 2025 *)
PROG
(PARI) zetamult([3, 3]) \\ Charles R Greathouse IV, Jan 21 2016
CROSSREFS
Cf. A072691 (zetamult(1,1)), A197110 (zetamult(2,2)), A258983 (zetamult(3,2)), A258984 (4,2), A258985 (5,2), A258947 (6,2), A258986 (2,3), A258988 (4,3), A258982 (5,3), A258989 (2,4), A258990 (3,4), A258991 (4,4).
Sequence in context: A112027 A174400 A178079 * A174254 A384755 A024404
KEYWORD
nonn,cons,easy
AUTHOR
STATUS
approved