关键词:
Carmichael number
Fermat's Little Theorem
Li Shanlan
摘要:
In the western world there is this myth that the ancient Chinese knew a special case of Fermat's Little Theorem and erroneously took it as a criterion for primality, namely, that n is a prime if and only if 2(n-1) - 1 is divisible by n. This article discusses how this myth might have come about, in particular tells the story of an investigation on number theory by Li Shanlan in the mid 19(th) century. The discussion touches upon the social history of the incident in connection with the polarized attitude different foreigners took towards Chinese mathematics at the time.