Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.
The motivation for starting Project Euler, and its continuation, is to provide a platform for the inquiring mind to delve into unfamiliar areas and learn new concepts in a fun and recreational context.
Well, I started solving some of them using C# and the .Net Framework. I’m trying out Mercurial for source control, and you can currently find, look at, download and fork my code at BitBucket.
Since I don’t have any executables, but two assemblies full of tests instead, I run my code inside Visual Studio 2010 using a handy VS Add-In called TestDriven.Net.
Below is a list where you can see what problems I have solved so far. The ones with a link attached are also blogged about.
Problems
| 1 | Add all the natural numbers below one thousand that are multiples of 3 or 5. | Solved |
|---|---|---|
| 2 | Find the sum of all the even-valued terms in the Fibonacci sequence which do not exceed four million. | Solved |
| 3 | Find the largest prime factor of a composite number. | Solved |
| 4 | Find the largest palindrome made from the product of two 3-digit numbers. | Solved |
| 5 | What is the smallest number divisible by each of the numbers 1 to 20? | Solved |
| 6 | What is the difference between the sum of the squares and the square of the sums? | Solved |
| 7 | Find the 10001st prime. | Solved |
| 8 | Discover the largest product of five consecutive digits in the 1000-digit number. | Solved |
| 9 | Find the only Pythagorean triplet, {a, b, c}, for which a + b + c = 1000. | Solved |
| 10 | Calculate the sum of all the primes below two million. | Solved |
| 11 | What is the greatest product of four numbers on the same straight line in the 20 by 20 grid? | Solved |
| 12 | What is the value of the first triangle number to have over five hundred divisors? | Solved |
| 13 | Find the first ten digits of the sum of one-hundred 50-digit numbers. | Solved |
| 14 | Find the longest sequence using a starting number under one million. | Solved |
| 16 | What is the sum of the digits of the number  ? |
Solved |
| 25 | What is the first term in the Fibonacci sequence to contain 1000 digits? | Solved |
