How to compose mathematical papers in engineering conferences?
Yes, it is considered good form, in mathematics, to have at least a sentence to introduce 'named' theorems, lemmas and definitions and navigate the reader through the results. And an "introduction" section --- you can dispense with the conclusions.

Sometimes in this kind of venues you are allowed to put the proofs of your theorems and lemmas in an appendix (which doesn't count against your page limit). Ask the organizers if it is the case.

If not, then leave everything as it is; it seems that you have no better solution (assuming that you have already tried to save as much vertical space as you can).