PROJECT EULER #50

Link to Project Euler problem 50

The prime 41, can be written as the sum of six consecutive primes:
41 = 2 + 3 + 5 + 7 + 11 + 13
This is the longest sum of consecutive primes that adds to a prime below one-hundred.
The longest sum of consecutive primes below one-thousand that adds to a prime, contains 21 terms, and is equal to 953.
Which prime, below one-million, can be written as the sum of the most consecutive primes?

using System;
using System.Collections.Generic;

namespace project_euler
{
   class Program
   {
       static void Main()
       {
           //Problem 50
           DateTime start = DateTime.Now;
           List<int> primes = GeneratePrimes(1000000);
           int max = 0, total = 0, initial = 0;
           for (int i = 0; i < 5; i++)
           {
               int sum = 0, number = 0;
               for (int j = i; j < primes.Count; j++)
               {
                   sum += primes[j];
                   if (sum > 1000000) break;
                   number++;
                   if (primes.Contains(sum))
                       if (number > total)
                       {
                           total = number;
                           max = sum;
                           initial = primes[i];                                                     
                       }
               }
           }
           Console.WriteLine("{0} steps from {1} give {2}", total, initial, max);
           TimeSpan time = DateTime.Now - start;
           Console.WriteLine("This took {0}", time);
           Console.ReadKey();
       }
       public static bool IsPrime(int n)
       {
           if (n < 2)
               return false;
           if (n == 2)
               return true;
           for (long i = 2; i <= Math.Sqrt(n); i++)
               if (n % i == 0)
                   return false;
           return true;
       }
       public static List<int> GeneratePrimes(int n)
       {
           var primes = new List<int> { 2, 3 };
           for (int i = 5; i <= n; i += 2)
           {
               if (IsPrime(i))
                   primes.Add(i);
           }
           return primes;
       }
   }
}