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A244843
Decimal expansion of the integral of log(2+x^2+y^2)/((1+x^2)*(1+y^2)) dx dy over the square [0,1]x[0,1].
2
5, 6, 9, 5, 9, 6, 1, 5, 8, 1, 8, 3, 6, 1, 4, 5, 0, 6, 2, 3, 6, 4, 5, 5, 5, 3, 6, 7, 2, 7, 1, 7, 4, 6, 9, 0, 1, 0, 7, 8, 7, 6, 1, 2, 6, 8, 2, 1, 2, 2, 8, 7, 8, 3, 6, 8, 2, 8, 1, 8, 4, 0, 8, 1, 2, 4, 8, 5, 2, 3, 0, 0, 2, 5, 0, 2, 9, 9, 1, 8, 1, 1, 6, 1, 4, 0, 5, 6, 5, 7, 4, 2, 2, 2, 7, 2, 4, 5, 8, 6, 8
OFFSET
0,1
COMMENTS
The computation of this integral is given by Bailey & Borwein as an example of the use of CAS packages (and additional tools) to simplify large symbolic expressions.
LINKS
D. H. Bailey and J. M. Borwein, Experimental computation as an ontological game changer, 2014, see p. 5.
D. H. Bailey, J. M. Borwein and A. D. Kaiser, Automated Simplification of Large Symbolic Expressions
Eric Weisstein's MathWorld, Clausen's Integral.
Eric Weisstein's MathWorld, Polylogarithm.
FORMULA
Pi^2/8*log(2) - 7/48*zeta(3) + 11/24*Pi*Cl2(Pi/6) - 29/24*Pi*Cl2(5*Pi/6), where Cl2 is the Clausen function Cl2(t) = Sum_{n>0} sin(n*t)/n^2.
EXAMPLE
0.56959615818361450623645553672717469010787612682122878368281840812485230025...
MATHEMATICA
Clausen2[x_] := Im[PolyLog[2, Exp[x*I]]]; Pi^2/8*Log[2] - 7/48*Zeta[3] + 11/24*Pi*Clausen2[Pi/6] - 29/24*Pi*Clausen2[5*Pi/6] // RealDigits[#, 10, 101]& // First
PROG
(PARI) Cl2(x)=imag(polylog(2, exp(x*I)));
Pi^2/8*log(2) - 7/48*zeta(3) + 11/24*Pi*Cl2(Pi/6) - 29/24*Pi*Cl2(5*Pi/6) \\ Charles R Greathouse IV, Aug 27 2014
CROSSREFS
Cf. A261027 (Cl_2(Pi/6)), A261028 (Cl_2(5*Pi/6)).
Sequence in context: A019598 A340565 A197283 * A118261 A246749 A357471
KEYWORD
cons,nonn
AUTHOR
STATUS
approved