彥彥
@Hello881
說
Sat, Jan 22, 2022 2:24 PM
以前問過 11111 的質因數分解，印象最有邏輯性的推論方式如下：
11111
= 99999 / 9
= (102400-2401)/9
= (320^2 - 49^2)/9
= (320+49)(320-49)/9
= 369 × 271 / 9
= 41 × 271
掰噗~
@baipu
說
Sat, Jan 22, 2022 2:24 PM
你說了算~
載入新的回覆
11111
= 99999 / 9
= (102400-2401)/9
= (320^2 - 49^2)/9
= (320+49)(320-49)/9
= 369 × 271 / 9
= 41 × 271