(a-1)(a)(a+1)=24
(a²-1)a=24 24=2³x3 = 2 x3 x 2²
nr sunt 2, 3 si 4 2x3x4=24
(a-1)(a)(a+1)=720
(a²-1)a=720 720=2⁴x3²x5 =(2³) x (3²) x (2x5)
nr sunt 8, 9 si 10 8x9x10=720
(a-1)(a)(a+1)=15600 15600=2⁴x3x5²x13 = (2³x3) x(5²) x( 2x13)
(a²-1)a=15600
nr sunt 24, 25 si 26 24x25x26=15600
(a-1)(a)(a+1)=2803080 2803080=2³x3x5x7x47x71=(2²x5x7)x(3x47)x(2x71)
(a²-1)a=2803080
nr sunt 140 , 141 si 142 140x141x142=2803080
