THE MONTENEGRIN DICE GAME

It is said that the inhabitants of Montenegro have a little dice game that is both ingenious and well worth investigation. The two players first select two different pairs of odd numbers (always higher than `3`) and then alternately toss three dice. Whichever first throws the dice so that they add up to one of his selected numbers wins. If they are both successful in two successive throws it is a draw and they try again. For example, one player may select `7` and `15` and the other `5` and `13`. Then if the first player throws so that the three dice add up `7` or `15` he wins, unless the second man gets either `5` or `13` on his throw.

The puzzle is to discover which two pairs of numbers should be selected in order to give both players an exactly even chance.