A242055 Decimal expansion of c, a constant appearing in the asymptotic lower bound of the size of a restricted difference set.

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

Offset

1,2

References

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.28 p. 188.

Links

Table of n, a(n) for n=1..103.

Steven R. Finch, Errata and Addenda to Mathematical Constants. 2.28 p. 26.

Formula

c = sqrt(2*(1 - sin(theta)/theta)), where theta is the smallest positive zero of tan(t)-t (theta = A115365).

Example

1.560277942041879702102077381568463756373995745949542538537...

Mathematica

digits = 103; theta = t /. FindRoot[Tan[t] == t, {t, 4}, WorkingPrecision -> digits+5]; c = Sqrt[2*(1 - Sin[theta]/theta)]; RealDigits[c, 10, digits] // First

Crossrefs

Cf. A115365.

Sequence in context: A100220 A011440 A375957 * A178591 A179588 A092161

Adjacent sequences: A242052 A242053 A242054 * A242056 A242057 A242058

Keyword

nonn,cons

Author

Jean-François Alcover, Aug 13 2014

Status

approved