When counting forward, numbers increase by 1 from left to right.

Fill in the missing numbers in the line.

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If we call numbers in order, starting from 1, we count forward. In this case, each next number is 1 greater than the previous one. It is called forward counting or counting in ascending order.

Knowing the difference between adjacent numbers, we can continue the sequence, and find any missing numbers in it. To do this, add 1 to the known number. Let's look at the example below.

There is a sequence with two known numbers - 42 and 43. 43 is 42+1. Knowing this, we can find the number that follows 43. Thus, we add 1 to 43.

In the same way, we can fill in all gaps in the number line.

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