单双数是指整数中能够被2整除的数（双数或偶数）和不能被2整除的数（单数或奇数）。以下是单双数的列表：
单数（奇数）:
1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49
双数（偶数）:
2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50
希望这能帮助你理解单双数的概念