Which Renaissance typography type has mathematically perfect sized letters?

Antica

Explanation:

Antica is a form of typography or fonts in both web applications and desktop or mobile devices such as computers and smartphones. It was originally designed during the art period, and considered to be characterized by its mathematically perfect sized letters.

Hence, in this case, Renaissance typography type that has mathematically perfect sized letters is known as ANTICA

i'm not sure i completely understand your question, but i will do my best.

i think the answer you are looking for is sequence. (see below)

a repeated melodic fragment would be best defined as repetition, while repeated chords (different or the same) could be a chord progression. however, you then mentioned the chord and melodic fragment beginning on higher or lower pitches, in that case, the answer could be best defined as a sequence. the definition of a sequence is as follows: "the restatement of a motif or longer melodic (or harmonic) passage at a higher or lower pitch in the same voice."

let me know if this !