Ciorapel a descoperit ruinele unei cetati vechi .Ajutal sa o restaureze.Descopera regula si continua fiecare sir. 998,996,994

Răspuns :

998,996,994,992,990,988,986,984,982,980,978,976,974,972,970,968,966,964,962,960,958,956,954,952,950, 948,946,944,942,940,939,936,934,932,930,928,926,924,922,920,918,916,914,912,910,908,906,904,902,900.......
Pana la cât trebuie?