This is another challenge I did to see if I was capable of completing it without using external resources/references.

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

namespace FibonacciSequence
{
    class Program
    {
        static void Main(string[] args)
        {
            int countTo;
            while (true)
            {
                Console.Write("Please enter how many numbers of the Fibonacci sequence"
                                   + "\nyou would like to generate (1-47): ");
                countTo = int.Parse(Console.ReadLine());
                if (countTo < 1)
                {
                    Console.WriteLine();
                    Console.WriteLine("Please enter a number of one or more.");
                    Console.WriteLine();
                }
                else if (countTo > 47)
                {
                    Console.WriteLine();
                    Console.WriteLine("Please enter a number of 47 or less.");
                    Console.WriteLine();
                }
                else break;
            }
            Console.WriteLine();
            Generate(countTo);
            Console.WriteLine();
            Console.WriteLine("Press any key to terminate program...");
            Console.Read();
        }

        public static void Generate(int input)
        {
            if (input == 1) Console.WriteLine("0");
            else if (input == 2) Console.WriteLine("0, 1");
            else
            {
                int value1 = 0;
                int value2 = 1;
                int value3;
                Console.Write("0, 1, ");
                for (int i = 0; i <= input - 4; i++)
                {
                    value3 = value1 + value2;
                    Console.Write(value3 + ", ");
                    value1 = value2;
                    value2 = value3;
                }
                value3 = value1 + value2;
                Console.Write(value3);
            }
        }
    }
}

But then I made some improvements to the program; this time I had to look up a few things.

Changes:
-Instead of writing all the numbers on one continuous line, it separates them with new lines
-It can now generate up to 94 numbers rather than 47
-I made the code a bit cleaner
-I added a check in case the input isn't a valid number
-Commas are added to represent thousands, millions, etc.

using System;
using System.Text;

namespace FibonacciSequence
{
    class Program
    {
        static void Main(string[] args)
        {
            int countTo;
            while (true)
            {
                Console.Write("Please enter how many numbers of the Fibonacci sequence"
                                   + "\nyou would like to generate (1-94): ");
                if (int.TryParse(Console.ReadLine(), out countTo))
                {
                    if (countTo >= 1 && countTo <= 94)
                    {
                        break;
                    }
                }
                Console.WriteLine("\nInvalid input. Please enter a number between 1 and 94.\n");
            }
            Console.WriteLine();
            Generate(countTo);
            Console.WriteLine("\nPress any key to terminate program...");
            Console.Read();
        }

        public static void Generate(int input)
        {
            if (input == 1) Console.WriteLine("0");
            else if (input == 2) Console.WriteLine("0\n1");
            else
            {
                ulong value1 = 0;
                ulong value2 = 1;
                ulong value3;
                Console.Write("0\n1\n");
                for (int i = 0; i <= input - 4; i++)
                {
                    value3 = value1 + value2;
                    Console.Write(value3.ToString("#,#" + "\n"));
                    value1 = value2;
                    value2 = value3;
                }
                value3 = value1 + value2;
                Console.Write(value3.ToString("#,#" + "\n"));
            }
        }
    }
}