C(13,5,2) <=10

Method of construction: lex covering

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