质数有23,29,31,37,41,43...
奇数有21.23.25.27.29.31.33.35.37.39.41.43.45.48...
合数有:.21.22.24.25.26.2728.29.30..37.41.43.47...
偶数有20.22.24.26.28.30.32.34.36.38.40.42.44.46.48.50..
质数有23,29,31,37,41,43...
奇数有21.23.25.27.29.31.33.35.37.39.41.43.45.48...
合数有:.21.22.24.25.26.2728.29.30..37.41.43.47...
偶数有20.22.24.26.28.30.32.34.36.38.40.42.44.46.48.50..