Cmn (m above m and below n)

Multiply m by (m- 1), (m-2) and (m-3) until 1, and the number is recorded as a.

Then multiply n by (n- 1) by (n-2) by (n-3) until the number of m is multiplied continuously, and this number is recorded as B.

Finally, b divided by a, that's it.

Example: To calculate C34, first calculate 3*2* 1=6.

Then 4*3*2=24.

The last 24/6=4

Calculate C35, first calculate 3*2* 1=6.

Then 5*4*3=60.

The last 60/6= 10

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