The associated Legendre functions P n m ( x ) {\displaystyle P_{n}^{m}(x)} are polynomials which are most conveniently defined in terms of derivatives of the Legendre polynomials:
P n m ( x ) = ( 1 − x 2 ) m / 2 d m d x m P n ( x ) {\displaystyle P_{n}^{m}(x)=(1-x^{2})^{m/2}{\frac {d^{m}}{dx^{m}}}P_{n}(x)}
The first associated Legendre polynomials are:
etc.