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A048834
Decimal expansion of Sum_{n >= 2} (K(n)/n!), where K(n) is A002034.
3
1, 7, 1, 4, 0, 0, 6, 2, 9, 3, 5, 9, 1, 6, 1, 6, 0, 2, 2, 7, 2, 7, 7, 4, 3, 8, 4, 5, 4, 1, 9, 0, 3, 3, 7, 5, 4, 8, 3, 1, 5, 9, 7, 9, 2, 1, 7, 1, 8, 9, 5, 7, 4, 0, 9, 0, 0, 1, 2, 1, 4, 6, 5, 7, 3, 9, 5, 2, 1, 0, 8, 9, 9, 3, 8, 8, 2, 9, 1, 7, 6, 6, 5, 4, 5, 6, 7, 8, 5, 1, 2, 8, 9, 8, 0, 8, 9, 0, 6, 0, 5, 8, 7
OFFSET
1,2
COMMENTS
This constant was proved to be irrational by Cojocaru and Cojocaru (1996). - Amiram Eldar, Jul 07 2021
LINKS
Charles Ashbacher, Smarandache Sequences, Stereograms and Series, Hexis (2005).
Ion Cojocaru and Sorin Cojocaru, The Second Constant of Smarandache, Smarandache Notions Journal, Vol. 7, No. 1-2-3 (1996), pp. 119-120.
Eric Weisstein's World of Mathematics, Smarandache Constants.
EXAMPLE
1.71400629359161602272774384541903375483159792171895...
MAPLE
Digits := 80 ; A002034:=[1, 2, 3, 4, 5, 3, 7, 4, 6, 5, 11, 4, 13, 7, 5, 6, 17, 6, 19, 5, 7, 11, 23, 4, 10, 13, 9, 7, 29, 5, 31, 8, 11, 17, 7, 6, 37, 19, 13, 5, 41, 7, 43, 11, 6, 23, 47, 6, 14, 10, 17, 13, 53, 9, 11, 7, 19, 29, 59, 5, 61, 31, 7, 8, 13, 11, 67, 17, 23, 7, 71, 6, 73, 37, 10, 19, 11, 13, 79, 6, 9, 41, 83, 7]; sma := 0.0 ; for n from 2 to nops(A002034) do sma := sma + A002034[n]/factorial(n) ; od ; # R. J. Mathar, Apr 13 2006
MATHEMATICA
K[n_] := Module[{k = 1}, While[True, If[Divisible[k!, n], Return[k], k++]]];
N[Sum[K[n]/n! , {n, 2, 200}], 103] // RealDigits // First (* Jean-François Alcover, Nov 17 2020 *)
CROSSREFS
Sequence in context: A104621 A331900 A176439 * A010504 A242132 A011450
KEYWORD
nonn,cons
AUTHOR
Charles T. Le (charlestle(AT)yahoo.com)
EXTENSIONS
More terms from R. J. Mathar, Apr 13 2006
More terms from Jean-François Alcover, Nov 17 2020
STATUS
approved