Improve a comment and fix return type of as_int()
Add MIT license and AUTHORS file
Add .mailmap file
Travis: print full output on failure
Implement mul_expand()
Test it
Better printing
Implement simplifications in pow()
Fix a bug
Simplification
Implement missing branch in mul_expand_two
Rename expand() -> pow_expand()
Implement expand()
Simplify tests
Improve expand()
Implement add_expand()
Improve expand, add another test
Improve add_expand()
Speedup expansion
Add a note