Update README.md

Author: OssieLin

README.md

@@ -8,7 +8,7 @@ These primality tests fail for certain numbers called **pseudoprimes**.\
 My research focuses on analyzing the class of Perrin-type primality tests- **Lucas-Type Sequence**:
 
 ## [Lucas-Type Sequence](https://oeis.org/wiki/Lucas_sequences)
-Each primality test is a sequence with two parameters$$c_0, c_1$$
+Each primality test is a sequence with two parameters: $$c_0, c_1$$
 $$V_{n+2} = c_1 V_{n+1} + c_0 V_{n}, \quad V_{0} = 2, \quad V_{1} = c_1$$
 
 If p is prime, then we have the congruence $$V_{p}\equiv V_{1}(mod\quad p)$$