Denote the set of all \binom{10}{3} = 120 triples (size-3 subsets) of the 10 drives by T, or to be explicit, % import itertools % T = itertools.combinations(range(1, 11), 3) % print '\{', ','.join('\{ %d, %d, %d \}' % t for t in T), '\}' T = \{ \{ 1, 2, 3 \},\{ 1, 2, 4 \},\{ 1, 2, 5 \},\{ 1, 2, 6 \},\{ 1, 2, 7 \},\{ 1, 2, 8 \},\{ 1, 2, 9 \},\{ 1, 2, 10 \},\{ 1, 3, 4 \},\{ 1, 3, 5 \},\{ 1, 3, 6 \},\{ 1, 3, 7 \},\{ 1, 3, 8 \},\{ 1, 3, 9 \},\{ 1, 3, 10 \},\{ 1, 4, 5 \},\{ 1, 4, 6 \},\{ 1, 4, 7 \},\{ 1, 4, 8 \},\{ 1, 4, 9 \},\{ 1, 4, 10 \},\{ 1, 5, 6 \},\{ 1, 5, 7 \},\{ 1, 5, 8 \},\{ 1, 5, 9 \},\{ 1, 5, 10 \},\{ 1, 6, 7 \},\{ 1, 6, 8 \},\{ 1, 6, 9 \},\{ 1, 6, 10 \},\{ 1, 7, 8 \},\{ 1, 7, 9 \},\{ 1, 7, 10 \},\{ 1, 8, 9 \},\{ 1, 8, 10 \},\{ 1, 9, 10 \},\{ 2, 3, 4 \},\{ 2, 3, 5 \},\{ 2, 3, 6 \},\{ 2, 3, 7 \},\{ 2, 3, 8 \},\{ 2, 3, 9 \},\{ 2, 3, 10 \},\{ 2, 4, 5 \},\{ 2, 4, 6 \},\{ 2, 4, 7 \},\{ 2, 4, 8 \},\{ 2, 4, 9 \},\{ 2, 4, 10 \},\{ 2, 5, 6 \},\{ 2, 5, 7 \},\{ 2, 5, 8 \},\{ 2, 5, 9 \},\{ 2, 5, 10 \},\{ 2, 6, 7 \},\{ 2, 6, 8 \},\{ 2, 6, 9 \},\{ 2, 6, 10 \},\{ 2, 7, 8 \},\{ 2, 7, 9 \},\{ 2, 7, 10 \},\{ 2, 8, 9 \},\{ 2, 8, 10 \},\{ 2, 9, 10 \},\{ 3, 4, 5 \},\{ 3, 4, 6 \},\{ 3, 4, 7 \},\{ 3, 4, 8 \},\{ 3, 4, 9 \},\{ 3, 4, 10 \},\{ 3, 5, 6 \},\{ 3, 5, 7 \},\{ 3, 5, 8 \},\{ 3, 5, 9 \},\{ 3, 5, 10 \},\{ 3, 6, 7 \},\{ 3, 6, 8 \},\{ 3, 6, 9 \},\{ 3, 6, 10 \},\{ 3, 7, 8 \},\{ 3, 7, 9 \},\{ 3, 7, 10 \},\{ 3, 8, 9 \},\{ 3, 8, 10 \},\{ 3, 9, 10 \},\{ 4, 5, 6 \},\{ 4, 5, 7 \},\{ 4, 5, 8 \},\{ 4, 5, 9 \},\{ 4, 5, 10 \},\{ 4, 6, 7 \},\{ 4, 6, 8 \},\{ 4, 6, 9 \},\{ 4, 6, 10 \},\{ 4, 7, 8 \},\{ 4, 7, 9 \},\{ 4, 7, 10 \},\{ 4, 8, 9 \},\{ 4, 8, 10 \},\{ 4, 9, 10 \},\{ 5, 6, 7 \},\{ 5, 6, 8 \},\{ 5, 6, 9 \},\{ 5, 6, 10 \},\{ 5, 7, 8 \},\{ 5, 7, 9 \},\{ 5, 7, 10 \},\{ 5, 8, 9 \},\{ 5, 8, 10 \},\{ 5, 9, 10 \},\{ 6, 7, 8 \},\{ 6, 7, 9 \},\{ 6, 7, 10 \},\{ 6, 8, 9 \},\{ 6, 8, 10 \},\{ 6, 9, 10 \},\{ 7, 8, 9 \},\{ 7, 8, 10 \},\{ 7, 9, 10 \},\{ 8, 9, 10 \} \} ...