var mul_table = [
        512,512,456,512,328,456,335,512,405,328,271,456,388,335,292,512,
        454,405,364,328,298,271,496,456,420,388,360,335,312,292,273,512,
        482,454,428,405,383,364,345,328,312,298,284,271,259,496,475,456,
        437,420,404,388,374,360,347,335,323,312,302,292,282,273,265,512,