People seem to be using the modulus function a fair amount (it's been in Copasi for ages, translated to ugly-looking mathML), so it would be good to add those two functions to the list of allowable MathML in L3v2 core.
EDIT: Updated to make this the general tracking item for 'what MathML elements should we add to the allowable subset of MathML'
EDIT #2: After some discussion, we now have three options:
1) Add all the MathML we discussed at HARMONY to L3v2 core (basically, all the functions that are either useful or easy to implement), and put other sets into MathML-only packages.
2) Add only quotient, rem, max, min, and implies to L3v2 core (basically, all the functions that are both useful and easy to implement); put other sets into MathML-only packages.
3) Add no new MathML to core; instead, add all the MathML we discussed at HARMONY including quotient, rem, etc. into domain-specific MatHML-only packages.