9 2d 1 July 8, 2019 16 32 64 128 9 2d 15 9 2d 17 9 2d 19 2d 9 11 9 2d ≥ 1 9 2d ≤ 1 9 2d 4 1 d 3 2d 9 + 13 10 21 8d 9 2d 1 4 6d 9 2d 10 2d 9 5d 2d 1 10d 9 /( 2d 2 3 15d 9 2d 3d 7 2d 9 1
