Number Before 4030: Identify the Predecessor

To solve the problem, we need to determine the number that comes immediately before 4030 in a sequential series.

Step 1: Understand that consecutive numbers differ by one. If we have a number $x$, the next number after $x$ is $x + 1$.

Step 2: Given that 4030 is the number after the unknown number, we can set up the relationship:
Let the unknown number be $x$, then:

$x + 1 = 4030$

Step 3: Solve for $x$ by subtracting 1 from both sides of the equation:

$x = 4030 - 1$

Step 4: Perform the calculation:

$x = 4029$

Therefore, the number you are looking for is $4029$.