feat(pascal): math mistake

Co-authored-by: MaoShizhong <122839503+MaoShizhong@users.noreply.github.com>

Author: nik-rev

19_pascal/README.md

@@ -9,7 +9,7 @@ also be said to be `0, 1, 0`
 First row: `[1]`
 Second row: `[0+1, 1+0]` or simply `[1, 1]`
 Third row: `[0+1, 1+1, 1+0]` or simply `[1, 2, 1]`
-Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 2, 2, 1]`
+Fourth row: `[0+1, 1+2, 2+1, 1+0]` or simply `[1, 3, 3, 1]`
 ... 
 
 The pattern continues forever.