The MathPad 3.04 distribution file contains the application, documentation and examples.
[MathPad3.04.dmg] (2.2M) Disk Image
[MathPad3.04.zip] (1.4M) Zip Archive
Both archives contain the same files. Download whichever you prefer. A mountable disk image is typically used for software installation but MathPad does not need to install any auxiliary files. There is no fancy installer to run so either format will work.