In this game players take turns choosing a starting value from a set of available numbers, and then alternately factorise until it is fully decomposed into its prime factors. Players score the number of points given by each number chosen or factor entered. However, there is a catch. Since factors occur as pairs, although the choosing player scores the value chosen, their opponent scores points according to the other factor in the pair. So, for example, it is not only important to recognise that 5 is a factor of 95: for best play a player must calculate 19 as the other factor, and so score 19 points while only giving 5 away.
Hit the Setup… button to configure play — as two players or teams, or compete against the computer. Play continues until all values have been fully factorised, and the winner is the player with most points.