Seven Up

In this game, you deal out cards in an overlapping row as in Decade. If the last card is a Seven, you can discard it. Otherwise, you can also discard any consecutive set of cards ending with the last card, if they add up to an even multiple of seven (Jacks count as 11, Queens as 12, and Kings as 13). You win if you can discard the whole deck.

I figured out the win rate of this game even without writing a program! The deck starts out with the ranks adding up to an even multiple of 7 (364 to be exact; 4 suits of 91 each). Every time you discard, the remaining cards will still total an even multiple of 7. So, after the final card is played, it is guaranteed that the total value of all the cards still in play will be an even multiple of seven, so you can discard them all and win every time! This is true no matter how many discarding opportunities you may have missed during the rest of the game.

In order to fix this game, there needs to be some limit either on the number of cards which can be discarded at a time (seven?), or else a maximum multiple of seven that can be discarded.

Any comments are welcome, please send to Mark Masten at:

Last modified January 29, 2022

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