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A397289
Decimal expansion of Sum_{k>=1} (-1)^(k+1) * AH(k,4)/k, where AH(k,4) = A120296(k)/A334585(k) is the k-th alternating harmonic (or skew-harmonic) number of order 4.
3
7, 1, 5, 5, 7, 5, 7, 4, 3, 0, 6, 4, 5, 8, 7, 9, 4, 9, 3, 2, 7, 5, 4, 6, 1, 2, 3, 5, 7, 6, 3, 5, 8, 5, 4, 8, 5, 9, 0, 5, 1, 7, 7, 9, 7, 4, 9, 2, 9, 3, 4, 8, 5, 7, 1, 0, 7, 3, 1, 7, 6, 6, 3, 5, 5, 9, 4, 3, 6, 7, 1, 2, 9, 2, 7, 7, 6, 5, 7, 0, 1, 7, 3, 3, 7, 4, 3, 6, 3, 4, 0, 8, 2, 3, 3, 3, 3, 1, 4, 7, 8, 6, 5, 4, 4
OFFSET
0,1
FORMULA
Equals 91*zeta(5)/32 - 3*zeta(2)*zeta(3)/4 - log(2)*zeta(4).
EXAMPLE
0.715575743064587949327546123576358548590517797492934...
MATHEMATICA
RealDigits[91*Zeta[5]/32 - 3*Zeta[2]*Zeta[3]/4 - Log[2]*Zeta[4], 10, 120][[1]]
PROG
(PARI) 91*zeta(5)/32 - 3*zeta(2)*zeta(3)/4 - log(2)*zeta(4)
CROSSREFS
Sum_{k>=1} (-1)^(k+1) * AH(k,m)/k: A369884 (m=1), A397288 (m=2), this constant (m=4), A397290 (m=6), A397291 (m=8).
Sequence in context: A011478 A334072 A118307 * A379799 A351738 A178757
KEYWORD
nonn,cons
AUTHOR
Amiram Eldar, Jun 20 2026
STATUS
approved