C(20,14,4) = 10

Method of Construction: simple construction: multiple of smaller covering

Lower Bound: Todorov, JCTA, 1985

  3  4  6  7  8  9 10 13 14 16 17 18 19 20
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  1  2  3  4  5  7 10 11 12 13 14 15 17 20
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