20: Blackjack doubling strategy when doubling after splitting aces is allowed.19: Blackjack splitting strategy when a back-player is betting.
18: Basic strategy exceptions for three to six cards.16: Basic strategy when dealer exposes both cards.
20: Blackjack doubling strategy when doubling after splitting aces is allowed.19: Blackjack splitting strategy when a back-player is betting.
18: Basic strategy exceptions for three to six cards.16: Basic strategy when dealer exposes both cards.