A135821 Decimal expansion of sqrt(4*e - 1).

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

Offset

1,1

Links

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

Formula

Sqrt(Sum_{n>=1}((1/2)*n^3 + (1/2)*n + 1)/n!). - Alexander R. Povolotsky, Oct 01 2011

Example

3.1421532925425807337006835045314966069705383584581530419234...

Maple

Digits:=100: evalf(sqrt(4*exp(1)-1)); # Wesley Ivan Hurt, Nov 24 2016

Mathematica

RealDigits[Sqrt[4E - 1], 10, 105][[1]] (* Alonso del Arte, Oct 01 2011 *)

Prog

(PARI) sqrt(suminf(n=1, (1/2*n^3+1/2*n+1)/n!)); \\ Michel Marcus, Mar 09 2014

Crossrefs

Sequence in context: A190457 A179833 A131033 * A289205 A283866 A134545

Adjacent sequences: A135818 A135819 A135820 * A135822 A135823 A135824

Keyword

nonn,cons

Author

Alexander R. Povolotsky, Mar 06 2008

Extensions

Offset corrected R. J. Mathar, Jan 26 2009

Status

approved