Show HN: Our first game for Facebook, a math based puzzler

Our first Facebook game, Mexem, went live a few weeks ago. The idea of it is to find simple equations in a hexagon grid of numbers. The game matches chains of numbers (you can select with a trackpad or mouse, but it's a lot quicker with a mouse) when a valid equation is found. You don't need to select an operator - the game does that automatically. It supports four operators (+, -, /, and *) and can calculate multi or single digit answers from a selection of single digit hexes. The game rewards you with score multipliers or 'bombs' for making longer chains more quickly. There is also a 'Full House' bonus for each time the player uses the whole set of operators. Each game lasts for one minute.

The Mexem Facebook page is here: http://www.facebook.com/apps/application.php?id=126083207410955

or you can go straight to the app: http://apps.facebook.com/mexemgame/

Any suggestions for gaining more users and/or monetising the Facebook version would be appreciated (we also have an IOS version in the works, but it's on the sideline at the moment due to working on another project).

[For clarity: I (this username, Trouble) am the girlfriend of one of the two programmers who made the game. They're both very focused on making games and solving problems, so I suggested that I post Mexem here on HN for feedback on marketing and monetization. I will be making sure they see and respond to any comments and questions. Thank you!]