postulado 101 poligonos concavos ordenados 15
All polygon concave ordered full divided in fact congruent squares ( m, r, 2 ) greater than r m r greater than two, is separated into a rectangle divided into congruent square and a square divided into congruent squares of order ( m, r-1 ) and ( m-1, r ) respectively, if and only if m and r are consecutive numbers.