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A059191
Engel expansion of 1/gamma, (gamma is the Euler-Mascheroni constant A001620) = 1.73245.
1
1, 2, 3, 3, 6, 10, 20, 46, 226, 1836, 3719, 14308, 17262, 129530, 945152, 1535786, 2229882, 3560447, 9434930, 20957352, 102311436, 312567415, 449243761, 4362956254, 12000988888, 22909186976, 29969826721
OFFSET
1,2
COMMENTS
Cf. A006784 for definition of Engel expansion.
REFERENCES
F. Engel, Entwicklung der Zahlen nach Stammbruechen, Verhandlungen der 52. Versammlung deutscher Philologen und Schulmaenner in Marburg, 1913, pp. 190-191.
LINKS
G. C. Greubel and T. D. Noe, Table of n, a(n) for n = 1..1000[Terms 1 to 300 computed by T. D. Noe; Terms 301 to 1000 computed by G. C. Greubel, Dec 27 2016]
F. Engel, Entwicklung der Zahlen nach Stammbruechen, Verhandlungen der 52. Versammlung deutscher Philologen und Schulmaenner in Marburg, 1913, pp. 190-191. English translation by Georg Fischer, included with his permission.
P. Erdős and Jeffrey Shallit, New bounds on the length of finite Pierce and Engel series, Sem. Theor. Nombres Bordeaux (2) 3 (1991), no. 1, 43-53.
MATHEMATICA
EngelExp[A_, n_] := Join[Array[1 &, Floor[A]], First@Transpose@
NestList[{Ceiling[1/Expand[#[[1]] #[[2]] - 1]], Expand[#[[1]] #[[2]] - 1]/1} &, {Ceiling[1/(A - Floor[A])], (A - Floor[A])/1}, n - 1]];
EngelExp[N[EulerGamma^2, 7!], 100] (* Modified by G. C. Greubel, Dec 27 2016 *)
CROSSREFS
Cf. A098907.
Sequence in context: A079888 A165257 A368223 * A124063 A054630 A049875
KEYWORD
nonn,easy,nice
AUTHOR
STATUS
approved