C(16,10,2) = 4

Method of Construction: simple construction: multiple of smaller covering

 1  2  3  4  5  9 10 11 12 13 
 1  2  6  7  8  9 10 14 15 16 
 1  3  4  5  8  9 11 12 13 16 
 3  4  5  6  7 11 12 13 14 15