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A270556 Denominators of r-Egyptian fraction expansion for the Euler-Mascheroni constant (EulerGamma), where r(k) = 1/(2k-1). 1
2, 5, 19, 6299, 35743868, 4259425108512909, 41287268337787979739179113461425, 8252465584213549846948406832722177155507422403521413106477917012 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Suppose that r is a sequence of rational numbers r(k) <= 1 for k >= 1, and that x is an irrational number in (0,1).  Let f(0) = x, n(k) = floor(r(k)/f(k-1)), and f(k) = f(k-1) - r(k)/n(k).  Then x = r(1)/n(1) + r(2)/n(2) + r(3)/n(3) + ... , the r-Egyptian fraction for x.

See A269993 for a guide to related sequences.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..11

Eric Weisstein's World of Mathematics, Egyptian Fraction

Index entries for sequences related to Egyptian fractions

EXAMPLE

Euler-Mascheroni constant = 1/(1*2) + 1/(3*5) + 1/(5*19) + 1/(7*6299) + ...

MATHEMATICA

r[k_] := 1/(2k-1); f[x_, 0] = x; z = 10;

n[x_, k_] := n[x, k] = Ceiling[r[k]/f[x, k - 1]]

f[x_, k_] := f[x, k] = f[x, k - 1] - r[k]/n[x, k]

x = EulerGamma; Table[n[x, k], {k, 1, z}]

CROSSREFS

Cf. A269993, A005408.

Sequence in context: A177875 A187602 A260140 * A059079 A177494 A136900

Adjacent sequences:  A270553 A270554 A270555 * A270557 A270558 A270559

KEYWORD

nonn,frac,easy

AUTHOR

Clark Kimberling, Apr 03 2016

STATUS

approved

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Last modified December 12 15:11 EST 2019. Contains 329960 sequences. (Running on oeis4.)