ID 
Title 
Solutions and Code 
1 
Multiples of 3 and 5 
Solution 
2 
Even Fibonacci numbers 
Solution 
3 
Largest prime factor 
Solution  Code 
4 
Largest palindrome product 
Solution  Code 
5 
Smallest multiple 
Solution  Code 
6 
Sum square difference 
Solution 
7 
10001st prime 
Solution  Code 
8 
Largest product in a series 

9 
Special Pythagorean triplet 
Solution  Code 
10 
Summation of primes 
Solution  Code 
11 
Largest product in a grid 

12 
Highly divisible triangular 
Solution  Code 
13 
Large sum 
Solution  Code 
14 
Longest Collatz sequence 
Solution  Code 
15 
Lattice paths 

16 
Power digit sum 

17 
Number Letter Counts 

18 
Maximum Path Sum I 

19 
Counting Sundays 

20 
Factorial Digit Sum 
