A222391 - OEIS

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

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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