Sample invariants
x,y,z are variables; a,b,c are constants
Invariants over numbers
- unary: x = a, a ? x ? b, x ? a(mod b), …
- n-ary: x ? y, x = ay + bz + c, x = max(y, z), …
Invariants over sequences
- unary: sorted, invariants over all elements
- with sequence: subsequence, ordering
- with scalar: membership