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A019774 Decimal expansion of sqrt(e). 31
1, 6, 4, 8, 7, 2, 1, 2, 7, 0, 7, 0, 0, 1, 2, 8, 1, 4, 6, 8, 4, 8, 6, 5, 0, 7, 8, 7, 8, 1, 4, 1, 6, 3, 5, 7, 1, 6, 5, 3, 7, 7, 6, 1, 0, 0, 7, 1, 0, 1, 4, 8, 0, 1, 1, 5, 7, 5, 0, 7, 9, 3, 1, 1, 6, 4, 0, 6, 6, 1, 0, 2, 1, 1, 9, 4, 2, 1, 5, 6, 0, 8, 6, 3, 2, 7, 7, 6, 5, 2, 0, 0, 5, 6, 3, 6, 6, 6, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..20000

FORMULA

Sqrt(e) = Sum_(n=0, inf) 1/(2^n n!) = Sum_(n=0, inf) 1/(2n)!!. - Daniel Forgues, Apr 17 2011

sqrt(e) = 1 + sum(n>0, prod(i=1..n, 1/(2n) )). - Ralf Stephan, Sep 11 2013

EXAMPLE

1.6487212707001281468486507878141635716537761007101480115750...

MATHEMATICA

RealDigits[N[Sqrt[E], 200]][[1]] (*From Vladimir Joseph Stephan Orlovsky, Feb 21 2011*)

PROG

(PARI) { default(realprecision, 20080); x=sqrt(exp(1)); for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b019774.txt", n, " ", d)); } [From Harry J. Smith, May 01 2009]

CROSSREFS

Cf. A058281 for continued fraction for Sqrt(e).

Sequence in context: A197833 A176786 A077669 * A195434 A199815 A155906

Adjacent sequences:  A019771 A019772 A019773 * A019775 A019776 A019777

KEYWORD

nonn,cons

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified September 15 23:11 EDT 2014. Contains 246792 sequences.