Calculation is a weird solitaire card game. It's different than any other solitaire card game I've played. There are 5 piles at the top of the game screen that you can place cards into in any order, but you can only take the top card off the pile, and you CAN NOT move cards between the piles.
The foundations are also really weird. When placing cards onto the foundations, suit does not matter. The card you can place must be X more than the card currently on top of the foundation, where X is the card placed next to the foundation. In other words, if the card next to the pile is an Ace, the card you place on top must be one more than the card currently on the top of the foundation. If it is a 2, the card you place must be 2 more than the card currently on top. To make the process of figuring this out easier, I put the next card that must go on top of the pile, in a field to the left of the foundation.