. ---+------------------------------+-------------+------------
. 0 [1] 1
. 1 [2] 2 2
. 2 [2,3] 6 3
. 3 [4,5] 20 5
. 4 [2,5,7] 70 7
. 5 [4,9,7] 252 9
. 6 [4,3,7,11] 924 11
. 7 [8,3,11,13] 3432 13
. 8 [2,9,5,11,13] 12870 13
. 9 [4,5,11,13,17] 48620 17
. 10 [4,11,13,17,19] 184756 19
. 11 [8,3,7,13,17,19] 705432 19
. 12 [4,7,13,17,19,23] 2704156 23
. 13 [8,25,7,17,19,23] 10400600 25
. 14 [8,27,25,17,19,23] 40116600 27
. 15 [16,9,5,17,19,23,29] 155117520 29
. 16 [2,9,5,17,19,23,29,31] 601080390 31
. 17 [4,27,5,11,19,23,29,31] 2333606220 31
. 18 [4,3,25,7,11,19,23,29,31] 9075135300 31
. 19 [8,3,25,7,11,23,29,31,37] 35345263800 37
. 20 [4,9,5,7,11,13,23,29,31,37] 137846528820 37 .