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A306617
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Decimal expansion of a constant related to the asymptotics of A324425.
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2
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8, 2, 8, 8, 5, 9, 5, 7, 9, 6, 6, 9, 2, 7, 9, 2, 8, 6, 6, 9, 7, 2, 2, 9, 0, 2, 0, 7, 7, 5, 1, 0, 3, 0, 2, 6, 7, 6, 9, 1, 0, 5, 7, 5, 5, 9, 7, 7, 1, 2, 1, 1, 4, 5, 2, 4, 4, 0, 4, 0, 3, 3, 1, 7, 9, 5, 7, 1, 8, 3, 4, 3, 0, 2, 2, 1, 4, 7, 1, 8, 3, 7, 7, 6, 7, 1, 1, 3, 1, 1, 8, 9, 2, 7, 8, 7, 3, 0, 4, 0, 5, 4, 9, 3, 0, 9
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OFFSET
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0,1
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COMMENTS
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Ulrich Neumann found a closed form, see the "Mathematica Stack Exchange" link.
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LINKS
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FORMULA
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Equals limit_{n->infinity} (A324425(n)^(1/n^3))/n^2.
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EXAMPLE
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0.828859579669279286697229020775103026769105755977121145244040331795...
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MAPLE
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evalf(exp(integrate(log(x^2 + y^2 + z^2), x = 0..1, y = 0..1, z = 0..1)), 20);
evalf(exp(integrate(-2 + 2*sqrt(y^2 + z^2) * arctan(1/sqrt(y^2 + z^2)) + log(1 + y^2 + z^2), y = 0..1, z = 0..1)), 20);
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MATHEMATICA
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ixr = Exp[Integrate[1/3 (Log[1 + Sec[fi]^2] + (-7 + 3 Log[1 + Sec[fi]^2]) Sec[fi]^2 + 2 (Pi - 2 ArcTan[Sec[fi]]) Sec[fi]^3), {fi, 0, Pi/4}]]; Chop[N[ixr, 120]] (* A program by Ulrich Neumann added by Vaclav Kotesovec, Mar 03 2019. The calculation takes several minutes. *)
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PROG
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(PARI) exp(intnum(z=0, 1 , intnum(y=0, 1, intnum(x=0, 1, log(x^2 + y^2 + z^2)))))
(PARI) exp(intnum(z=0, 1 , intnum(y=0, 1, -2 + 2*sqrt(y^2 + z^2) * atan(1/sqrt(y^2 + z^2)) + log(1 + y^2 + z^2))))
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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