Occurrence statistics

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

class MainClass {
    static void Main() {
        var limit = 100000;
        var chances = 10;
        var possibleOutcomes = "HT";
        var patterns = new List<string> { "HTT", "HTH" };
        var patternFormat = $"{{0,-{patterns.Select(x => x.Length).Max()}}}";
        
        Console.WriteLine($"Settings: \n{limit,10} Iterations (for precision)\n{string.Join(", ", possibleOutcomes.ToCharArray()),10} are the possible outcomes");
        Console.WriteLine("Checking for bad data...");
        for(var i = 0; i < patterns.Count; i++)
        {
            var pattern = patterns[i];
            if(!pattern.Any())
            {
                patterns.RemoveAt(i--);
                Console.WriteLine("  Removed empty pattern");
                
            }
            else if(pattern.Except(possibleOutcomes).Any())
            {
                patterns.RemoveAt(i--);
                Console.WriteLine($"  {pattern} contains illegal characters");
            }
        }
        
        Console.WriteLine("Calculating...");
        
        var found = new bool[patterns.Count];
        var counts = new int[patterns.Count][];
        for(var i = 0; i < patterns.Count; i++)
        {
            counts[i] = new int[limit];
        }
        Func<int,string> statsStats = (i) =>
        {
            var sum = 0.0;
            var length = patterns[i].Length;
            var list = new List<int>();
            for(int j = length; j < 1000; j++)
                list.Add(counts[i].Count(j.Equals));
            return string.Concat(
                "(",
                string.Join(", ", list.Take(chances).Select(x => $"{Math.Round(1000.0*x/limit)/10.0,5:0.0}%")),
                " ) ",
                list.TakeWhile(x => (sum += (1.0*x/limit)) <= 0.90).Count()
                );
        };
        var stats = (Func<int,string>)((i) => $"{string.Format(patternFormat,patterns[i])} avg {Math.Round(counts[i].Average()),-2} {statsStats(i)}");
        var rand = new Random();
        
        for(int i = 0; i < limit; i++)
        {
            for(var j = 0; j < patterns.Count; j++)
                found[j] = false;
            var serie = new StringBuilder();
            
            while(found.Any(false.Equals))
            {
                serie.Append(possibleOutcomes[rand.Next(possibleOutcomes.Length)]);
                
                for(var pattern = 0; pattern < patterns.Count; pattern++)
                    if(serie.Length >= patterns[pattern].Length 
                    && !found[pattern])
                        if(Regex.Match(serie.ToString(), $"{patterns[pattern]}$").Success)
                        {
                            found[pattern] = true;
                            counts[pattern][i] = serie.ToString().Length;
                        }
                
            }
        }
        
        for(int i = 0; i < patterns.Count; i++)
            Console.WriteLine(stats(i));
    }
}