Riddles, brain puzzles and mathematical problems

[Froge]

A received an odd number because there is no way for odd + 2n to equal 14.

B received an odd number greater than or equal to 7 (and less than 12). That's because he knew everyone had different numbers even before listening to A, which is only possible if he received 7, 9, or 11 (those are the numbers which result in A and C being different).

Now it's simply a matter of brute forcing the solution:

1. B received 7.
A: 1 -> C = 6
A: 3 -> C = 4
A: 5 -> C = 2

2. B received 9.
A: 1 -> C = 4
A: 3 -> C = 2.

3. B received 11.
A: 1 -> C = 2.

This shows C must have received one of 2, 4, or 6.

Given that C knows what number he received, the only way he can be certain of what the other two are is if he received 6, as that is the only number that has only one combination above matching the statements of A and B.

So A = 1, B = 7, C = 6.