Test Euler number:
ln (e (x)) = -20.00000_00000_04151_96027
ln (e (x)) = -19.00000_00000_01297_12726
ln (e (x)) = -18.00000_00000_00172_58303
ln (e (x)) = -17.00000_00000_00040_25656
ln (e (x)) = -16.00000_00000_00080_99257
ln (e (x)) = -15.00000_00000_00018_92228
ln (e (x)) = -14.00000_00000_00009_4814
ln (e (x)) = -13.00000_00000_00001_91378
ln (e (x)) = -12.00000_00000_00001_58827
ln (e (x)) = -11.00000_00000_00000_55758
ln (e (x)) = -10.00000_00000_00000_03382
ln (e (x)) = -9.00000_00000_00000_07696
ln (e (x)) = -8.00000_00000_00000_02629
ln (e (x)) = -7.00000_00000_00000_00877
ln (e (x)) = -6.00000_00000_00000_00122
ln (e (x)) = -5.00000_00000_00000_00098
ln (e (x)) = -4.00000_00000_00000_0002
ln (e (x)) = -3.00000_00000_00000_00018
ln (e (x)) = -2.00000_00000_00000_00002
ln (e (x)) = -1.00000_00000_00000_00001
ln (e (x)) = 0
ln (e (x)) = 0.99999_99999_99999_99999
ln (e (x)) = 1.99999_99999_99999_99999
ln (e (x)) = 2.99999_99999_99999_99999
ln (e (x)) = 3.99999_99999_99999_99999
ln (e (x)) = 4.99999_99999_99999_99999
ln (e (x)) = 5.99999_99999_99999_99999
ln (e (x)) = 6.99999_99999_99999_99999
ln (e (x)) = 7.99999_99999_99999_99999
ln (e (x)) = 8.99999_99999_99999_99999
ln (e (x)) = 9.99999_99999_99999_99999
ln (e (x)) = 10.99999_99999_99999_99999
ln (e (x)) = 11.99999_99999_99999_99999
ln (e (x)) = 12.99999_99999_99999_99999
ln (e (x)) = 13.99999_99999_99999_99999
ln (e (x)) = 14.99999_99999_99999_99999
ln (e (x)) = 15.99999_99999_99999_99999
ln (e (x)) = 16.99999_99999_99999_99999
ln (e (x)) = 17.99999_99999_99999_99999
ln (e (x)) = 18.99999_99999_99999_99999
ln (e (x)) = 19.99999_99999_99999_99999
, computation time is  0.170457139 s.