title: Calculating pi using infinite series in C#
body: <p>I tried to write the following program in C# to calculate pi using infinite recursion, but I keep getting confused about integer/double/decimal division.</p>
  
  <p>I really have no clue why this isn't working, so pardon me for my lack of understanding of strongly typed stuff, as I'm still learning C#.</p>
  
  <p>Thanks in advance!</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Text;
  
  namespace ConsoleApplication1
  {
      class Program
      {
          public static int Main(string[] args)
          {
              int numeratornext = 2;
              int denominatornext = 5;
  
              decimal findto = 100.0M;
              decimal pi = 0.0M;
              decimal halfpi = 1.0M;
              int seriesnum = 1;
              int seriesden = 3;
  
              for (int i = 0; i &lt; findto; i++)
              {
                  halfpi += Decimal.Divide((decimal)seriesnum, (decimal)seriesden);
                  //System.Console.WriteLine(Decimal.Divide((decimal)seriesnum, (decimal)seriesden).ToString());
                  seriesnum *= numeratornext;
                  seriesden *= denominatornext;
                  numeratornext++;
                  denominatornext += 2;
              }
  
              pi = halfpi * 2;
  
              System.Console.WriteLine(pi.ToString());
              System.Console.ReadLine();
              return 0;
          }
      }
  }
  </code></pre>