Sequence Members

using System;
using System.Linq;

class SequenceDec
{
    private static void Main()
    {
        int n = 0;
        Console.WriteLine("Point out how many members of the sequence you'd like to be displayed below: ");
        string input = Console.ReadLine();
        bool wrongInput = !int.TryParse(input, out n);
        if (wrongInput)
        {
            Console.WriteLine("Sorry pal! Either you cannot differ number from anything else, or you are trying to bug my program :) Well, you can try again later !!!");
        }
        else
        {
            int a = 2;
            while (true)
            {
                wrongInput = a <= n + 1;
                if (!wrongInput)
                {
                    break;
                }
                int evenOdd = a % 2;
                wrongInput = evenOdd == 0;
                if (wrongInput)
                {
                    Console.Write(string.Concat(a, ", "));
                }
                else
                {
                    Console.Write(string.Concat(a * -1, ", "));
                }
                a++;
            }
            Console.WriteLine();
        }
    }
}