diff --git a/TangDou/Topic/莫比乌斯函数.md b/TangDou/Topic/莫比乌斯函数.md
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--- a/TangDou/Topic/莫比乌斯函数.md
+++ b/TangDou/Topic/莫比乌斯函数.md
@@ -1,4 +1,5 @@
 ## 莫比乌斯函数
+https://blog.csdn.net/qq_49593247/article/details/120394226
 
 https://www.cnblogs.com/letlifestop/p/10262757.html