You have 3 cards, each labeled with consecutive integers n, n+1, and n+2, where n is unknown. All cards are placed face down. On your turn, you flip one card. After seeing its value, you can either 'stay' and keep that value, or 'flip' another card. If you choose to flip another card, you can again choose to 'stay' and keep that value, or flip the final card and keep its value. Design the optimal strategy for maximizing your expected value.