A257530 Decimal expansion of sqrt(Pi/sqrt(e)).

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

Offset: 1

Author

Stanislav Sykora, Apr 28 2015

Keywords

• nonn
• cons

Examples

			1.38038844704314297477341524672559127427077246556221079845024685...
		

Links

• Stanislav Sykora, Table of n, a(n) for n = 1..2000
• Eric Weisstein's World of Mathematics, Cosine Integral, Eq.20

Crossrefs

Cf. A000796, A001113, A096414.

Programs

Mathematica

RealDigits[N[Sqrt[Pi/Sqrt@ E], 120]] (* Michael De Vlieger, Apr 30 2015 *)

PARI

a = sqrt(Pi/sqrt(exp(1)))

Formula

Equals integral[-inf..+inf](exp(-x^2)*cos(k*x)) = sqrt(Pi/exp(k^2/2)), for k = 1.