A371801 Decimal expansion of Sum_{k>=0} (-1)^k / (k^2 + 2).
2, 7, 6, 1, 3, 2, 1, 6, 6, 5, 4, 4, 2, 3, 9, 3, 2, 3, 6, 1, 5, 9, 3, 2, 3, 3, 7, 2, 8, 2, 3, 3, 8, 9, 3, 7, 0, 6, 4, 4, 0, 9, 8, 0, 7, 7, 4, 3, 7, 6, 3, 8, 9, 5, 9, 1, 2, 8, 0, 3, 5, 1, 9, 7, 6, 5, 8, 8, 6, 9, 1, 5, 0, 6, 9, 5, 3, 6, 6, 8, 0, 0, 8, 6, 7, 1
Offset: 0
Examples
0.2761321665442393236159323372823389370644098...
Crossrefs
Cf. A329083.
Programs
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Mathematica
s = N[Sum[(-1)^k/(k^2 + 2), {k, 0, Infinity}], 120] First[RealDigits[s]]
Formula
Equals (1/4)*(1 + sqrt(2)*Pi*csch(Pi*sqrt(2))).