We look at the division of 513731 by 1 
The aim is to understand the frequency of 1 in 513731.

Advancing to step 1:
5 divided by 1 is 5 with a remainder of 0.
Write down 5 as next digit of the result. 
Result so far: 5.0
If we subtract 5 from 5, we get 0.
Take the next digit (1) from the dividend and append it to 0, then repeat: 1 / 1

Going ahead to step 2:
1 can be fit into 1 1 times, resulting in a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 51.0
Subtract 1 from 1 to get 0.
Bring next digit (3) of the dividend behind the 0 and repeat the process: 3 / 1

Step 3:
When dividing 3 by 1, we get 3 with a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 513.0
If we take 3 away from 3, we end up with 0.
Fetch the next digit (7) from the dividend, attach it to 0 and continue: 7 / 1

On to step 4:
1 goes into 7 7 times with a remainder of 0.
Put 7 as the next digit of the answer. 
Result so far: 5137.0
Subtract 7 from 7 to get 0.
Grab the next digit (3) from the dividend, add it to 0, then carry on: 3 / 1

Step 5:
1 can be fit into 3 3 times, resulting in a remainder of 0.
Write down 3 as next digit of the result. 
Result so far: 51373.0
The remainder is 0 after subtracting 3 from 3.
Append the next digit (1) from the dividend to 0 and continue with: 1 / 1

Going ahead to step 6:
1 can be fit into 1 1 times, resulting in a remainder of 0.
Write down 1 as next digit of the result. 
Result so far: 513731.0
Deduct 1 from 1 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 7:
The number 1 fits into 0 0 times, leaving a remainder of 0.
Write down 0 as next digit of the result. 
Result so far: 513731.0
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Moving on to step 8:
If we divide 0 by 1, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 513731.0
Subtract 0 from 0 to get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

The final result is 513731.0 with a remainder of 0.0.