List all the ordered pairs in the relation R a b a divides

List all the ordered pairs in the relation
R = {(a, b) | a divides b}
on the set {1, 2, 3, 4, 5, 6}.
(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6)
(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6) (2, 2) (2, 4) (2, 6)
(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6) (2, 2) (2, 4) (2, 6) (3, 3) (3, 6)
(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6) (2, 2) (2, 4) (2, 6) (3, 3) (3, 6) (4, 4) (5, 5)
(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6) (2, 2) (2, 4) (2, 6) (3, 3) (3, 6) (4, 4) (5, 5) (6, 6)

THIS IS A DISCRETE MATH QUESTION

Solution

We must list all (a,b) such that a divides b

(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6)
(2, 2) (2, 4) (2, 6)
(3, 3) (3, 6)
(4, 4) (5, 5)
(6, 6)