A game machine operable to execute a game program is communicatively
connected to a center server. In the center server, a first transmitter
transmits, to the game machine, first data indicating a settled play
amount out of a played amount which is represented by either an
accumulated number or time period that the game program has been
executed. In the game machine, a first storage is operable to store the
first data, a second storage is operable to store second data indicating
the played amount, and a third storage is operable to store third data
indicating an allowable unsettled play amount which represents either an
allowable number or time period of which the game program is executed
without settlement. In the game machine, a first receiver receives the
first data transmitted by the first transmitter, an updater updates the
first data stored in the first storage with the first data received by
the first receiver, and a controller controls the game machine based on
the first data stored in the first storage, the second data stored in the
second storage and the third data stored in the third storage.