一道中學數學競賽題

Starting with a four-digit integer that is not a multiple of 1000, an integer with fewer digits can be obtained by removing the leading digit and ignoring leading zeros. For example, removing the leading digit from 1023 gives the integer 23, and removing the leading digit from 2165 gives 165. How many integers from 1001 to 4999, inclusive, other than multiples of 1000, have the property that the integer obtained by removing the leading digit is a factor of the original integer

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• 試解： 15+14+14+13 = 56個？ -wxcfan123- ♂ (0 bytes) () 09/04/2023 postreply 17:35:53

• 應該更多些 -萬斤油- ♂ (0 bytes) () 09/04/2023 postreply 18:45:23

• 再試： 83 -wxcfan123- ♂ (0 bytes) () 09/04/2023 postreply 19:33:14

• 正確！ -萬斤油- ♂ (0 bytes) () 09/04/2023 postreply 20:13:17