# algebra

posted by
**arjit**
.

For how many pairs of positive integers n and k with n and k less than or equal to 20, is the number (2n)!(2k)!n!k!(n+k)! an integer?

posted by
**arjit**
.

For how many pairs of positive integers n and k with n and k less than or equal to 20, is the number (2n)!(2k)!n!k!(n+k)! an integer?