2. Folding sequences. a) Find the folding sequences for the an- gles of a regular 17-gon, a regular 257-gon and, you guessed it, a regular 65537-gon (evil laugh!).

6. 7, 0, -7, -14, ... Recursive: Explicit:

Discrete Math: Q# 1. How many strings of 9 letters can be created if the first and last letter must be the same? Is this 26^8 * 25?  Q#2. How many ways can a president, a vice-president, and a treasurer be chosen from a committee of 20 people? Is this 1140? I got this using the combinatorics definition using P(20,3)=20!/3!(20-3)1 Or is it 20!/(20-3)!=6840? I'm not sure which one to use. Q#3. How many numbers are there between 5 and 157 that are divisible by 3? Is this 52-3+1=50? I'm just going over some practice questions and want to make sure I'm on the right track. Thanks :)