Subsets of fixed size 2-subsets of{I,2,3}:{I,2},{1,3},{2,3} k-uniform () ={TCS|IT=k (-( “n choose k”Subsets of fixed size 2-subsets of { 1, 2, 3 }: {1, 2}, {1, 3}, {2, 3} ￾S k ⇥ k-uniform = {T ￾ S | |T| = k} “n choose k” ✓n k ◆ = ￾ ￾ ￾ ￾ ✓[n] k ◆￾ ￾ ￾ ￾