4 8 x 15 2 26 xy 20 July 8, 2019 16 32 64 128 4 8 x 15 2 26 xy lớn hơn 20 4 x 8 x 15 x 16 x 23 x 42 15 x 4 - 2 15 x 42 x 13 4 15 6 x 8 10 3
