Повернення до головоломок

Яка максимальна кількість ферзів можна розмістити на шахівниці так, щоб вони не атакували один одного? На дошці розміром n * n?

Відповідь: 1, при n = 1, 2; 2, при n = 3; n, при n> = 4. Разом на стандартній дошці 8 * 8 - 8:

  1 2 3 4 5 6 7 8
  ___ ___ ___ ___ ___ ___ ___ ___
 h |  |  |  |  |  |  |  Ф |  |
  --- --- --- --- --- --- --- ---
 g |  |  |  |  |  Ф |  |  |  |
  --- --- --- --- --- --- --- ---
 f |  |  |  Ф |  |  |  |  |  |
  --- --- --- --- --- --- --- ---
 e |  Ф |  |  |  |  |  |  |  |
  --- --- --- --- --- --- --- ---
 d |  |  |  |  |  |  Ф |  |  |
  --- --- --- --- --- --- --- ---
 c |  |  |  |  |  |  |  |  Ф |
  --- --- --- --- --- --- --- ---
 b |  |  Ф |  |  |  |  |  |  |
  --- --- --- --- --- --- --- ---
 a |  |  |  |  Ф |  |  |  |  |
  --- --- --- --- --- --- --- ---