Date: Oct 23, 2012 8:52 PM
Author: Edward
Subject: Congruence Question

So now I'm moving on and learning about congruence for the first time. Trying to take it all in and did some example problems to sharpen my skills, but I have two questions.

List all congruence classes for congruence mod 9, giving the most usual and one other name for each. Is this right?

-27 -18 -9 0 9 18 27 36 45 54 63 72 81 90
-26 -17 -8 1 10 19 28 37 46 55 64 73 82 91
-25 -16 -7 2 11 20 29 38 47 56 65 74 83 92
-24 -15 -6 3 12 21 30 39 48 57 66 75 84 93
-23 -14 -5 4 13 22 31 40 49 58 67 76 85 94
-22 -13 -4 5 14 23 32 41 50 59 68 77 86 95
-21 -12 -3 6 15 24 33 42 51 60 69 78 87 96
-20 -11 -2 7 16 25 34 43 52 61 70 79 88 97
-19 -10 -1 8 17 26 35 44 53 62 71 80 89 98

2.Use Fermat's Little Theorem to compute
3^508 (mod 509), 3^509(mod 509) and 3^512 (mod 509)

Any ideas for question 2? I'm lost