@PatrickLeder Basically, for 4: you have 6 valid triples, each of which can be "filled out" with any one card, making 90 total options. For 5, the same applies, but you have 15 options and then 14 options. I assume order didn't matter, so combination over permutation
@PatrickLeder I think it should be .735% for 3, 2.95% for 4, and 14.7% for 5.
For 3 cards: (6)/(18 choose 3)
For 4: (6 * 15)/(18 choose 4
For 5: (6 * 15 * 14)/(18 choose 5)