基本介紹
設k>1,p是一個奇素數,k|(p-1),q=(p-1)/k,則稱符號
![k次剩餘符號](/img/3/06e/wZwpmL0YzN3UTMxkTM0YTN1UTM1QDN5MjM5ADMwAjMwUzL5EzL3IzLt92YucmbvRWdo5Cd0FmLzE2LvoDc0RHa.jpg)
![k次剩餘符號](/img/2/9f3/wZwpmL4UzM0IDM4IDOzYTN1UTM1QDN5MjM5ADMwAjMwUzLygzL1QzLt92YucmbvRWdo5Cd0FmLwE2LvoDc0RHa.jpg)
![k次剩餘符號](/img/9/dcd/wZwpmL1QTO5ITM1kDOzYTN1UTM1QDN5MjM5ADMwAjMwUzL5gzLxMzLt92YucmbvRWdo5Cd0FmL0E2LvoDc0RHa.jpg)
為模p的 k次剩餘符號,這裡表示n 對模p的絕對最小剩餘 。(模p絕對的最小剩餘組成的完全剩餘系是指)。
k次剩餘符號的性質
![k次剩餘符號](/img/8/55c/wZwpmLygzNyYTNxIzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLyczL2QzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
k次剩餘符號有下述性質 :
![k次剩餘符號](/img/8/55c/wZwpmLygzNyYTNxIzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLyczL2QzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
1.p|n時,=0;
![k次剩餘符號](/img/8/55c/wZwpmLygzNyYTNxIzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLyczL2QzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
![k次剩餘符號](/img/9/964/wZwpmLwYjM2UTMzkDM0YTN1UTM1QDN5MjM5ADMwAjMwUzL5AzLxQzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
2.若n≡n(mod p),則=;
這是因為
![k次剩餘符號](/img/f/ec7/wZwpmL0ETN1IDN5gzNxUTN1UTM1QDN5MjM5ADMwAjMwUzL4czL0AzLt92YucmbvRWdo5Cd0FmLyE2LvoDc0RHa.jpg)
故有
![k次剩餘符號](/img/8/ee4/wZwpmLwgjM2QjN2MzNxUTN1UTM1QDN5MjM5ADMwAjMwUzLzczLxMzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
3.對任意整數n,n,有
![k次剩餘符號](/img/a/ed8/wZwpmL2ATM0kzM3gDM0YTN1UTM1QDN5MjM5ADMwAjMwUzL4AzLyIzLt92YucmbvRWdo5Cd0FmLyE2LvoDc0RHa.jpg)
4.若indn≡a(mod k),0≤a<k,則
![k次剩餘符號](/img/d/e2e/wZwpmL4IzMzETO0kDOzYTN1UTM1QDN5MjM5ADMwAjMwUzL5gzL2gzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
這是因為
![k次剩餘符號](/img/0/a02/wZwpmLyEDM1MTN4cDOzYTN1UTM1QDN5MjM5ADMwAjMwUzL3gzL3IzLt92YucmbvRWdo5Cd0FmLzE2LvoDc0RHa.jpg)
故有此結論 。
5.n是模p的k次剩餘的充分必要條件是
![k次剩餘符號](/img/5/8ef/wZwpmL3YTN0MzN0UDM0YTN1UTM1QDN5MjM5ADMwAjMwUzL1AzLwAzLt92YucmbvRWdo5Cd0FmLwE2LvoDc0RHa.jpg)
![k次剩餘符號](/img/a/1ff/wZwpmLwIzNzgzNyEzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLxczL3QzLt92YucmbvRWdo5Cd0FmL0E2LvoDc0RHa.jpg)
6.設n的標準分解式為,則
![k次剩餘符號](/img/4/aa5/wZwpmL0QzNxIDOxITM0YTN1UTM1QDN5MjM5ADMwAjMwUzLyEzLwEzLt92YucmbvRWdo5Cd0FmLzE2LvoDc0RHa.jpg)
![k次剩餘符號](/img/e/d62/wZwpmLwcDNxUTNxIzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLyczL2IzLt92YucmbvRWdo5Cd0FmL0E2LvoDc0RHa.jpg)
![k次剩餘符號](/img/8/55c/wZwpmLygzNyYTNxIzNzYTN1UTM1QDN5MjM5ADMwAjMwUzLyczL2QzLt92YucmbvRWdo5Cd0FmLxE2LvoDc0RHa.jpg)
若n<p,那么只要對每一個小於p的素數p,的值都知道,之值也就可求了 。