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A258989
Decimal expansion of the multiple zeta value (Euler sum) zetamult(2,4).
11
6, 7, 4, 5, 2, 3, 9, 1, 4, 0, 3, 3, 9, 6, 8, 1, 4, 0, 4, 9, 1, 5, 6, 0, 6, 0, 8, 2, 5, 7, 4, 2, 9, 9, 3, 9, 2, 7, 8, 3, 8, 4, 3, 6, 5, 1, 3, 7, 8, 8, 9, 5, 7, 9, 7, 0, 6, 9, 1, 7, 2, 2, 1, 4, 4, 3, 7, 7, 4, 8, 5, 8, 2, 4, 7, 7, 2, 4, 8, 5, 1, 9, 5, 6, 2, 5, 2, 6, 8, 8, 8, 5, 3, 4, 3, 0, 7, 9, 1, 2, 7, 8, 1
OFFSET
0,1
FORMULA
zetamult(2,4) = Sum_{m>=2} (Sum_{n=1..m-1} 1/(m^2*n^4)) = (25/12)*zeta(6) - zeta(3)^2.
Equals Sum_{i, j >= 1} 1/(i^4*j^2*binomial(i+j, i)). - Peter Bala, Aug 05 2025
EXAMPLE
0.67452391403396814049156060825742993927838436513788957970691722144377...
MATHEMATICA
RealDigits[(25/12)*Zeta[6] - Zeta[3]^2, 10, 103] // First
PROG
(PARI) zetamult([2, 4]) \\ 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), A258987 (3,3), A258988 (4,3), A258982 (5,3), A258990 (3,4), A258991 (4,4).
Sequence in context: A395807 A019932 A004447 * A005351 A098882 A254374
KEYWORD
nonn,cons,easy
AUTHOR
STATUS
approved