Sun 22 Sep 2024 : in double_exponential_arithmetic, applied new inverse,
  updated test_double_exponentials.adb.

Thu 19 Sep 2024 : in double_exponential_arithmetic, defined linear and
  quadratic inverses, tested by test_double_exponentials.

Tue 17 Sep 2024 : in double_exponential_arithmetic, defined the quadratic
  size extension, updated test_double_exponentials.adb.

Sat 14 Sep 2024 : in test_double_exponentials, generated random series
  with exponents in [1,2] to bound the extension degree to 2.

Tue 10 Sep 2024 : moved functions/procedures from test_double_exponentials
  to double_exponential_arithmetic.

Sun 8 Sep 2024 : in test_double_exponentials, added functions to compute
  extended series to ensure an accurate division.

Wed 4 Sep 2024 : bug fixed in calling test on multiplicative commutivativity.

Tue 3 Sep 2024 : experimented with extension degree in test on product in
  test_double_exponentials.adb.

Sun 1 Sep 2024 : added extension of series to compute higher order inverses.
  In test_double_exponentials.adb, fixed the computation of the exponents
  in the higher order series.

Tue 27 Aug 2024 : in double_exponential_arithmetic.adb, fixed superfluous
  zeros in the product.  Improved tests in test_double_exponentials.

Sun 25 Aug 2024 : added test on multiplicative commutativity to
  test_double_exponentials.  Improved double_exponential_arithmetic.adb.

Sat 24 Aug 2024 : improved tests with setting of quotient degree.

Thu 22 Aug 2024 : updated double_exponential_arithmetic for the product
  to work for series truncated at different degrees.
  Updated test_double_exponentials.  In double_exponential_arithmetic,
  added degree bounds as arguments, updated test_double_exponentials.adb.

Tue 20 Aug 2024 : new packages double_exponential_arithmetic and
  test_double_exponentials with code factored out from ts_expops.adb.
  Updated test_double_exponentials to verify that the Add/Sub operations
  work for series truncated at different degrees.
  Adjusted the documentation in double_exponential_arithmetic.ads.

Mon 19 Aug 2024 : improved test operations in ts_expops.adb.

Sun 18 Aug 2024 : improved accuracy of operations in ts_expops.adb.

Sat 17 Aug 2024 : new ts_expops.adb and exponentials.gpr.
  Added sum and product operations to ts_expops.adb.
