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A135005
Decimal expansion of 5/e.
2
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
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
Sequence in context: A170937 A058265 A357528 * A090734 A200614 A011467
KEYWORD
cons,nonn
AUTHOR
Omar E. Pol, Nov 15 2007
STATUS
approved