Updated Marathon A1's combo calculation algorithm.

Apparently the 1/6/15/28 multiplier comes from updating combo before calculating the multiplier, not something that gets independently multiplied.

tetris/modes/marathon_a1.lua

@@ -142,12 +142,12 @@ end
 
 function MarathonA1Game:updateScore(level, drop_bonus, cleared_lines)
 	if cleared_lines > 0 then
+		self.combo = self.combo + (cleared_lines - 1) * 2
 		self.score = self.score + (
 			(math.ceil((level + cleared_lines) / 4) + drop_bonus) *
-			cleared_lines * (cleared_lines * 2 - 1) * self.combo
+			cleared_lines * self.combo
 		)
-		self.lines = self.lines + cleared_lines
-		self.combo = self.combo + (cleared_lines - 1) * 2
+        self.lines = self.lines + cleared_lines
 	else
 		self.drop_bonus = 0
 		self.combo = 1