using System;
// Thanks to:
// http://b...content-available-to-author-only...x.net/2013/08/deterministic-miller-rabin-primality.html
// https://g...content-available-to-author-only...b.com/softwx/SoftWx.Numerics
 
namespace ConsoleApp1
{
// Найдите все натуральные n ∈ (0..1000), такие что 2ⁿ - n кратно 7.
// Find all natural numbers n ∈ (0..1000) such that 2ⁿ - n is a multiple of 7.
	class Program
	{
		// эта функция возвращает value ^ exponent % modulus
		static uint ModPow(uint value, uint exponent, ushort modulus)
		{
			uint result = 1;
			if ((exponent & 1) != 0) result = value;
			while ((exponent /= 2) != 0)
			{
				value = value * value % modulus;
				if ((exponent & 1) != 0)
					result = result * value % modulus;
			}
			return result;
		}
 
		static void Main()
		{
			for (uint i = 1; i < 1000; ++i)
				if (ModPow(2, i, 7) == i % 7)
					Console.Write(i + "\t");
			// Console.ReadKey(true);
		}
	}
}
 

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