We look at the division of 259329 by 81 
The aim is to understand the frequency of 81 in 259329.

Step 1:
The number 81 fits into 2 0 times, leaving a remainder of 2.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Subtracting 0 from 2 leaves us with 2.
Take the next digit (5) from the dividend and append it to 2, then repeat: 25 / 81

Advancing to step 2:
When dividing 25 by 81, we get 0 with a remainder of 25.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
The remainder is 25 after subtracting 0 from 25.
Bring next digit (9) of the dividend behind the 25 and repeat the process: 259 / 81

On to step 3:
When dividing 259 by 81, we get 3 with a remainder of 16.
Record the quotient 3 as the next digit in the result. 
Result so far: 3.0
Subtracting 243 from 259 leaves us with 16.
Bring next digit (3) of the dividend behind the 16 and repeat the process: 163 / 81

Let's proceed to step 4:
When dividing 163 by 81, we get 2 with a remainder of 1.
Write down 2 as next digit of the result. 
Result so far: 32.0
The remainder is 1 after subtracting 162 from 163.
Grab the next digit (2) from the dividend, add it to 1, then carry on: 12 / 81

On to step 5:
81 goes into 12 0 times with a remainder of 12.
The number 0 becomes the next digit in our result. 
Result so far: 320.0
If we subtract 0 from 12, we get 12.
Append the next digit (9) from the dividend to 12 and continue with: 129 / 81

On to step 6:
129 divided by 81 is 1 with a remainder of 48.
Put 1 as the next digit of the answer. 
Result so far: 3201.0
Subtracting 81 from 129 leaves us with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Going ahead to step 7:
81 goes into 480 5 times with a remainder of 75.
Record the quotient 5 as the next digit in the result. 
Result so far: 3201.5
Subtract 405 from 480 to get 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Moving on to step 8:
If we divide 750 by 81, we get 9 and a remainder of 21.
Write down 9 as next digit of the result. 
Result so far: 3201.59
Subtracting 729 from 750 leaves us with 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Let's proceed to step 9:
When dividing 210 by 81, we get 2 with a remainder of 48.
The number 2 becomes the next digit in our result. 
Result so far: 3201.592
If we take 162 away from 210, we end up with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Moving on to step 10:
If we divide 480 by 81, we get 5 and a remainder of 75.
Record the quotient 5 as the next digit in the result. 
Result so far: 3201.5925
If we subtract 405 from 480, we get 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Advancing to step 11:
If we divide 750 by 81, we get 9 and a remainder of 21.
The next digit of our result is 9. 
Result so far: 3201.59259
The remainder is 21 after subtracting 729 from 750.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

Going ahead to step 12:
The number 81 fits into 210 2 times, leaving a remainder of 48.
Use 2 as the next digit of our solution. 
Result so far: 3201.592592
If we take 162 away from 210, we end up with 48.
Since there are no more digits in the dividend, we add a zero to the remainder making it 480, and continue the process.

Going ahead to step 13:
When dividing 480 by 81, we get 5 with a remainder of 75.
Record the quotient 5 as the next digit in the result. 
Result so far: 3201.5925925
If we take 405 away from 480, we end up with 75.
Since there are no more digits in the dividend, we add a zero to the remainder making it 750, and continue the process.

Let's proceed to step 14:
If we divide 750 by 81, we get 9 and a remainder of 21.
Use 9 as the next digit of our solution. 
Result so far: 3201.59259259
Subtract 729 from 750 to get 21.
Since there are no more digits in the dividend, we add a zero to the remainder making it 210, and continue the process.

The final outcome is 3201.59259259, with a leftover of 2.1e-08.