Collection of mathematical formulas

No matter how you research it, you will find that a frequently used title for a collection of mathematical formulas* includes the word Handbook: e.g., Handbook of Mathematical Formulas or Handbook of Mathematical Functions or something similar.

Pocket Book (or pocketbook) is sometimes used in place of "handbook" to suggest that the material is easy to keep close at hand.

Other words that work are compendium and collection. You will almost never find these in the title of the book, but you will often find it in the description of the book.

A search on Amazon.com (books) for the subject "mathematical formulas" shows that "handbook" is often part of the title, and where it is not, then simply stating something like "Mathematical Formulas" in the title is sufficient. E.g., "CRC Standard Mathematical Tables and Formulae".

*(By the way, and off-topic, "formulae" and "formulas" are used interchangeably.)

Going by Google Books, it is recognised and acceptable to use formulary to refer to a collection of mathematical formulae. There is also a 1963 book titled, Mathematical Formulary, Including All Formulae Required for Mathematics I and II.

The etymonline entry for formulary notes:

Mathematical use is from 1796; use in chemistry is from c.1846.

So, you are on safe ground etymologically as well.