b (mod
d) if a mod d = r and b mod d = r, that is, a and b
leave the same remainder upon division by d. Note that this is the same as saying a
- b = kd for some integer k or equivalently d | (a - b). 4. Recall that a b (mod
d) if a mod d = r and b mod d = r, that is, a and b
leave the same remainder upon division by d. Note that this is the same as saying a
- b = kd for some integer k or equivalently d | (a - b).