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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
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.
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
Sequence in context: A177875 A187602 A260140 * A059079 A177494 A136900
KEYWORD
nonn,frac,easy
AUTHOR
Clark Kimberling, Apr 03 2016
STATUS
approved