# Products and Primes

### From PubNight

This dominos game is really complicated and should not be played when drunk. On the other hand playing when you are sober isn't much cop either.

The rules are dead easy - play as normal. It's the scoring that makes the brain ache.

You score for primes (i.e. 11 scores 11 points) but you score negative the sum of the factors of any other number (factors that are also products are broken down to their constituent factors!)) (9 for example scores -6 (i.e. 3+3). 24 scores -9 (3 + the products of 8 (ie 4 and 2 or 2,2 and 2))).

Confused? The following table shows the score value of each possible spot combination.

**Products and Primes Lookup Table**

Spots |
Scores |
Spots |
Scores |
Spots |
Scores |
Spots |
Scores |

0 |
0 |
13 |
13 |
26 |
-15 |
39 |
-16 |

1 |
1 |
14 |
-9 |
27 |
-9 |
40 |
-11 |

2 |
2 |
15 |
-8 |
28 |
-11 |
41 |
41 |

3 |
3 |
16 |
-8 |
29 |
29 |
42 |
-12 |

4 |
-4 |
17 |
17 |
30 |
-10 |
43 |
43 |

5 |
5 |
18 |
-11 |
31 |
31 |
44 |
-15 |

6 |
-5 |
19 |
19 |
32 |
-10 |
45 |
-11 |

7 |
7 |
20 |
-9 |
33 |
-14 |
46 |
-25 |

8 |
-6 |
21 |
-10 |
34 |
-19 |
||

9 |
-6 |
22 |
-13 |
35 |
-12 |
||

10 |
-7 |
23 |
23 |
36 |
-10 |
||

11 |
11 |
24 |
-9 |
37 |
37 |
||

12 |
-7 |
25 |
-10 |
38 |
-21 |