A226655 Decimal expansion of the 2nd Lebesgue constant L2.

1, 6, 4, 2, 1, 8, 8, 4, 3, 5, 2, 2, 2, 1, 2, 1, 1, 3, 6, 8, 7, 3, 6, 2, 7, 9, 8, 8, 9, 2, 2, 9, 4, 0, 3, 4, 4, 1, 8, 3, 8, 2, 3, 4, 5, 5, 4, 8, 4, 8, 8, 7, 4, 3, 0, 0, 7, 7, 6, 2, 0, 4, 2, 0, 7, 7, 0, 4, 6, 6, 5, 6, 9, 5, 5, 2, 5, 0, 2, 4, 9, 2, 8, 4, 5, 6, 4, 0, 8, 3, 3, 2, 7, 7, 0, 0, 7, 9, 7, 1

Offset

1,2

References

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, page 251.

Links

Table of n, a(n) for n=1..100.

Eric Weisstein's MathWorld, Lebesgue constants

Formula

(1/Pi)*integral_{t=0..Pi} abs(sin(5*t/2))/sin(t/2)

Equals 1/5 + sqrt(25 - 2*sqrt(5))/Pi.

Example

1.6421884352221211368736279889229403441838234554848874300776204207704665695525...

Mathematica

RealDigits[1/5 + Sqrt[25 - 2*Sqrt[5]]/Pi, 10, 100][[1]]

Crossrefs

Cf. A226654 (L1), A226656 (L3).

Sequence in context: A193076 A073449 A134300 * A340722 A199741 A125214

Adjacent sequences: A226652 A226653 A226654 * A226656 A226657 A226658

Keyword

cons,nonn

Author

Jean-François Alcover, Jun 14 2013

Status

approved