A222391 Decimal expansion of e^2/sqrt(Pi).

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

Offset

1,1

Links

G. C. Greubel, Table of n, a(n) for n = 1..5000

Formula

Equals A072334*A087197.

Equals decimal expansion of Sum_{n >= 1} 1/(Gamma(n/2)*Gamma((n+1)/2)).

Example

4.1688284832666922304213039077523102603866646811484996378300089546240432...

Maple

Digits:=100: evalf(exp(1)^2/sqrt(Pi)); # Wesley Ivan Hurt, Jan 09 2017

Mathematica

RealDigits[E^2/Sqrt[Pi], 10, 90][[1]]

Prog

(PARI) (exp(1))^2/sqrt(Pi) \\ G. C. Greubel, Jan 09 2017

Crossrefs

Cf. A072334, A087197, A222392.

Cf. A096789: Sum_{n >= 1} 1/(Gamma(n)*Gamma(n+1)).

Cf. A035009 (see fourth comment).

Sequence in context: A350106 A205137 A223534 * A332890 A154905 A124739

Adjacent sequences: A222388 A222389 A222390 * A222392 A222393 A222394

Keyword

nonn,cons

Author

Bruno Berselli, Mar 19 2013

Status

approved