A135005 Decimal expansion of 5/e.

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

Offset

1,2

Comments

The fraction of substituents which become isolated in a simple polymer model is 1/10 this number, see Flory 1939 (and 1936). - Charles R Greathouse IV, Nov 30 2012

Links

G. C. Greubel, Table of n, a(n) for n = 1..2000

Paul J. Flory, Intramolecular reaction between neighboring substituents of vinyl polymers, Journal of the American Chemical Society 61:6 (1939), pp. 1518-1521.

Paul J. Flory, Molecular size distribution in linear condensation polymers, Journal of the American Chemical Society 58:10 (1936), pp. 1877-1885.

Ovidiu Furdui, From Lalescu's sequence to a Gamma function limit, Gazette of the Australian Mathematical Society, Vol. 35, No. 5 (2008), pp. 339-344.

Formula

Equals 5/A001113 and 5*A068985. - Michel Marcus, Sep 17 2016

1/(2*e) = Integral_{x=1..oo} e^(-x^2) * x dx. - Amiram Eldar, Aug 03 2020

1/(2*e) = lim_{n->oo} n * ((n+1)!^(1/(n+1)) - n!^(1/n) - 1/e) (Furdui, 2008). - Amiram Eldar, Apr 20 2023

Example

5/e = 1.839397205857211607977618850807304337229...
1/(2*e) = 0.1839397205857211607977618850807304337229... (see Greathouse's comment).

Mathematica

RealDigits[5/E , 10, 50][[1]] (* G. C. Greubel, Sep 16 2016 *)

Prog

(PARI) 5/exp(1) \\ Michel Marcus, Sep 17 2016

Crossrefs

Cf. A001113, A068985.

Sequence in context: A170937 A058265 A357528 * A090734 A200614 A011467

Adjacent sequences: A135002 A135003 A135004 * A135006 A135007 A135008

Keyword

cons,nonn

Author

Omar E. Pol, Nov 15 2007

Status

approved