Solitaire! With a math twist.
Setup:
8 cards in your hand. 8 cards in 4 matched pairs in play.
Cards range in value from Ace=1 to King=13.
Objective:
Empty your hand of cards.
Play:
Form triads (three card groupings) using one of:
a. one card from your hand and a matched pair in play, or
b. two cards from your hand and one card in play.
A triad is a grouping of cards A, B, and C that satisfies one of the following:
a. A + B = C, or
b. A - B = C.