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A358450
Decimal expansion of 2*EllipticK(i) - EllipticE(i), reciprocal of A088375.
0
7, 1, 1, 9, 5, 8, 6, 5, 9, 7, 7, 8, 2, 6, 3, 8, 0, 1, 5, 1, 2, 4, 5, 8, 5, 4, 8, 8, 0, 5, 3, 9, 7, 7, 6, 7, 7, 2, 7, 7, 7, 1, 1, 4, 4, 1, 0, 7, 9, 8, 5, 8, 0, 2, 2, 7, 6, 5, 7, 3, 3, 7, 5, 4, 2, 7, 1, 9, 2, 6, 8, 6, 4, 6, 3, 2, 4, 9, 2, 8, 9, 6, 9, 7, 2, 0
OFFSET
0,1
FORMULA
Equals (a/b - b/a)*b^(1/2), where a = sqrt(2)*Gamma(5/4)^2 and b = Pi/4.
Equals sqrt(2) * (EllipticK(sqrt(2)/2) - EllipticE(sqrt(2)/2)).
Equals Integral_{x=0..Pi/2} cos(x)^2 / sqrt(1 + sin(x)^2).
EXAMPLE
0.7119586597782638015124585488053977677277711441...
MAPLE
Digits := 100: a := sqrt(2)*GAMMA(5/4)^2: b := Pi/4: evalf((a/b - b/a)*b^(1/2), Digits)*10^90: ListTools:-Reverse(convert(floor(%), base, 10));
MATHEMATICA
With[{a = Sqrt[2]*Gamma[5/4]^2, b = Pi/4}, RealDigits[(a/b - b/a)*b^(1/2), 10, 120][[1]]] (* Amiram Eldar, Nov 19 2022 *)
CROSSREFS
Cf. A088375.
Sequence in context: A305607 A229779 A050179 * A183352 A217510 A273506
KEYWORD
nonn,cons
AUTHOR
Peter Luschny, Nov 19 2022
STATUS
approved