A211879 Decimal expansion of constant C such that 1 = Sum_{k>=1} 1/C^(k^3).
1, 2, 3, 3, 8, 8, 8, 1, 4, 0, 3, 3, 7, 2, 7, 4, 1, 8, 8, 7, 5, 3, 5, 4, 7, 9, 2, 7, 3, 0, 8, 8, 6, 4, 1, 1, 5, 5, 0, 4, 7, 8, 2, 1, 4, 0, 1, 0, 9, 1, 2, 4, 2, 8, 9, 3, 1, 7, 6, 7, 7, 4, 8, 4, 5, 0, 7, 9, 9, 9, 0, 5, 6, 1, 9, 7, 8, 0, 3, 7, 4, 5, 5, 2, 7, 0, 9, 4, 0, 7, 6, 3, 9, 5, 5, 0, 8, 0, 1, 0, 8, 5, 8, 5, 0, 8, 6, 5, 6, 3, 7, 0, 1, 2, 5, 4
Offset: 1
Examples
C = 1.2338881403372741887535479273...
Crossrefs
Cf. A078975
Programs
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Maple
Digits:= 120: s:= convert(fsolve(sum(1/C^(k^3), k=1..infinity)=1, C=2)/10, string): seq(parse(s[n+1]), n=1..116); # Alois P. Heinz, Feb 13 2013
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Mathematica
digits = 116; f[x_?NumericQ] := NSum[1/x^(k^3), {k, 1, Infinity}, WorkingPrecision -> digits]; x /. FindRoot[f[x] == 1, {x, 3/2, 1, 2}, WorkingPrecision -> digits] // RealDigits[#, 10, digits]& // First (* Jean-François Alcover, Feb 20 2014 *)
Extensions
More terms from Alois P. Heinz, Feb 13 2013