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A300714
Decimal expansion of the total harmonic distortion (THD) of the sawtooth signal filtered by a 1st-order low-pass filter.
4
3, 6, 9, 4, 8, 6, 1, 8, 2, 0, 9, 5, 2, 0, 4, 3, 7, 3, 1, 2, 0, 0, 5, 4, 6, 9, 1, 4, 2, 3, 9, 7, 6, 9, 9, 3, 6, 6, 0, 2, 3, 6, 1, 5, 8, 6, 7, 9, 0, 8, 3, 8, 2, 5, 8, 9, 1, 6, 4, 9, 1, 8, 9, 0, 0, 1, 5, 1, 7, 9, 3, 1, 4, 2, 0, 0, 6, 6, 9, 9, 8, 3, 5, 0, 8, 2, 8, 4, 2, 5, 6, 1, 0, 2, 7, 6, 7, 4, 1, 8, 9, 8, 0
OFFSET
0,1
COMMENTS
See formula (33) in the Blagouchine & Moreau link.
LINKS
I. V. Blagouchine and E. Moreau, Analytic Method for the Computation of the Total Harmonic Distortion by the Cauchy Method of Residues. IEEE Trans. Commun., vol. 59, no. 9, pp. 2478-2491, 2011. PDF file.
FORMULA
Equals sqrt(Pi^2/3 - Pi*coth(Pi)).
EXAMPLE
0.3694861820952043731200546914239769936602361586790838...
MAPLE
evalf(sqrt((1/3)*Pi^2-Pi*coth(Pi)), 120)
MATHEMATICA
RealDigits[Sqrt[Pi^2/3 - Pi*Coth[Pi]], 10, 120][[1]]
PROG
(PARI) default(realprecision, 120); sqrt(Pi^2/3-Pi/tanh(Pi))
(MATLAB) format long; sqrt(pi^2/3-pi*coth(pi))
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
STATUS
approved