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From: Brian Gough <bjg@network-theory.co.uk>
To: GSL Discuss Mailing List <gsl-discuss@sourceware.org>
Subject: difficult region for gsl_sf_hyperg_1F1
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We have gsl_sf_hyperg1F1(-37.8, 2.01, 103.58) => -3.16661e+14 +/-
3.31+19 from the series.  Correct answer is -6.21927211009e17(*).
Does anyone know a better algorithm for this region?

http://savannah.gnu.org/bugs/?28267

(*) In pari:

poch(a,x) = { gamma(a+x)/gamma(a) }
t(a,b,x,k) = { (poch(a,k)/poch(b,k)) * (x^k)/(k!) }
suminf(k=0,t(-37.8,2.01,103.58,k))