---

using System;

class Program
{
    static void Main()
    {
        Console.Write("Введите ε: ");
        double eps = double.Parse(Console.ReadLine());

        double a_prev = 1;
        double a_curr = 0;
        int n = 1;

        Console.WriteLine($"a_{n} = {a_prev}");

        while (true)
        {
            n++;
            a_curr = 0.5 * (a_prev + 2.0 / a_prev);
            Console.WriteLine($"a_{n} = {a_curr}");

            if (Math.Abs(a_curr * a_curr - 2) < eps)
                break;

            a_prev = a_curr;
        }

        Console.WriteLine($"\nНаименьший номер: {n}");
        Console.ReadKey();
    }
}