17 Multiples of 8 plus 1 
6 Binary 5 digits 
17 

Multiples of 8 plus 1 
6 

Binary 5 digits 
5 

Matchsticks 
Binary 5 digits
Yup, Thanks :) context 
Multiples of 8 plus 1
Or 2k1 if you want to include 1. Well phrased solution, thanks. context 
Multiples of 8 plus 1
Yeah I think I might have done something closer to that the first time I did it, and this time through I went ahead and did it inductively. Very nice! context 
Binary 5 digits
Whoops, did the math for 6 digits while writing 5. 2^5 is the first 6 digit number in binary, not 2^6. Thanks! context 
6
7
Binary 5 digits
What is the base 10 equivalent of the highest 5 digit binary number?

Easy

17
29
Multiples of 8 plus 1
Squaring the first several odd numbers reveals the following pattern:
3 squared = 8 + 1
5 squared = 24 + 1
7 squared = 48 + 1
8, 24, and 48 are all multiples of 8. Does this pattern hold for all squa
...

Doable
