The "bottom numerals" don't mean much; they just indicate which note duration value is used for notating one beat. Unsual time signature means other than 2, 3

The "bottom numerals" don't mean much; they just indicate which note duration value is used for notating one beat. Unsual time signature means other than 2, 3 or 4 beats in a fundamental repeating block (usually correspondign to "measure").