Incomplete Gamma Function

   a           x         actual      gcf(a,x)     gammln(a)      gln
  0.10     1.581139     0.010104     0.010104    2.252713     2.252713
  0.50     3.535534     0.007834     0.007834    0.572365     0.572365
  1.00     5.000000     0.006738     0.006738    0.000000     0.000000
  1.10     5.244044     0.006657     0.006658   -0.049872    -0.049872
  2.00     7.071068     0.006855     0.006855    0.000000     0.000000
  6.00    12.247449     0.017406     0.017406    4.787492     4.787492
 11.00    16.583124     0.059573     0.059573   15.104413    15.104413
 41.00    44.821869     0.264029     0.264029  110.320641   110.320641