Epistemology
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Hermite polynomials, Orthogonal polynomials Find a combinatorial interpretation for the associated Legendre polynomials. Readings and links
Legendre polynomials
Rewriting the numerators and denominators
The numerators of the Legendre polynomial are given by the ways of taking paths on a square grid from (0,0) to (n,n) where the possible steps are East (weight x), North (weight 1), and East-North-East (weight -1). Associated Legendre Polynomials {$$P_l^m(x)=(-1)^m(1-x^2)^{m/2}\frac{\textrm{d}^m}{\textrm{dx}^m}(P_l(x))$$} P_0 {$P_{0}^{0}(x)=1$} P_1 {$P_{1}^{-1}(x)=-\begin{matrix}\frac{1}{2}\end{matrix}P_{1}^{1}(x)$} {$P_{1}^{0}(x)=x$} {$P_{1}^{1}(x)=-(1-x^2)^{1/2}$} P_2 {$P_{2}^{-2}(x)=\begin{matrix}\frac{1}{24}\end{matrix}P_{2}^{2}(x)$} {$P_{2}^{-1}(x)=-\begin{matrix}\frac{1}{6}\end{matrix}P_{2}^{1}(x)$} {$P_{2}^{0}(x)=\begin{matrix}\frac{1}{2}\end{matrix}(3x^{2}-1)$} {$P_{2}^{1}(x)=-3x(1-x^2)^{1/2}$} {$P_{2}^{2}(x)=3(1-x^2)$} P_3 {$P_{3}^{-3}(x)=-\begin{matrix}\frac{1}{720}\end{matrix}P_{3}^{3}(x)$} {$P_{3}^{-2}(x)=\begin{matrix}\frac{1}{120}\end{matrix}P_{3}^{2}(x)$} {$P_{3}^{-1}(x)=-\begin{matrix}\frac{1}{12}\end{matrix}P_{3}^{1}(x)$} {$P_{3}^{0}(x)=\begin{matrix}\frac{1}{2}\end{matrix}(5x^3-3x)$} {$P_{3}^{1}(x)=-\begin{matrix}\frac{3}{2}\end{matrix}(5x^{2}-1)(1-x^2)^{1/2}$} {$P_{3}^{2}(x)=15x(1-x^2)$} {$P_{3}^{3}(x)=-15(1-x^2)^{3/2}$} P_4 {$P_{4}^{-4}(x)=\begin{matrix}\frac{1}{40320}\end{matrix}P_{4}^{4}(x)$} {$P_{4}^{-3}(x)=-\begin{matrix}\frac{1}{5040}\end{matrix}P_{4}^{3}(x)$} {$P_{4}^{-2}(x)=\begin{matrix}\frac{1}{360}\end{matrix}P_{4}^{2}(x)$} {$P_{4}^{-1}(x)=-\begin{matrix}\frac{1}{20}\end{matrix}P_{4}^{1}(x)$} {$P_{4}^{0}(x)=\begin{matrix}\frac{1}{8}\end{matrix}(35x^{4}-30x^{2}+3)$} {$P_{4}^{1}(x)=-\begin{matrix}\frac{5}{2}\end{matrix}(7x^3-3x)(1-x^2)^{1/2}$} {$P_{4}^{2}(x)=\begin{matrix}\frac{15}{2}\end{matrix}(7x^2-1)(1-x^2)$} {$P_{4}^{3}(x)= - 105x(1-x^2)^{3/2}$} {$P_{4}^{4}(x)=105(1-x^2)^{2}$} P_5 {$P_{5}^{-5}(x)={1\over 3840}\left(\sqrt{1-x^2}\right)^{5}$} {$P_{5}^{-4}(x)={1\over 384}\left(\sqrt{1-x^2}\right)^{4}x$} {$P_{5}^{-3}(x)={1\over 384}\left(\sqrt{1-x^2}\right)^{3}(9x^{2}-1)$} {$P_{5}^{-2}(x)={1\over 16}\left(\sqrt{1-x^2}\right)^{2}(3x^{3}-1x)$} {$P_{5}^{-1}(x)={1\over 16}\left(\sqrt{1-x^2}\right)(21x^{4}-14x^{2}+1)$} {$P_{5}^{0}(x)={1\over 8}(63x^{5}-70x^{3}+15x)$} {$P_{5}^{1}(x)={-15\over 8}\left(\sqrt{1-x^2}\right)(21x^{4}-14x^{2}+1)$} {$P_{5}^{2}(x)={105\over 2}\left(\sqrt{1-x^2}\right)^{2}(3x^{3}-1x)$} {$P_{5}^{3}(x)={-105\over 2}\left(\sqrt{1-x^2}\right)^{3}(9x^{2}-1)$} {$P_{5}^{4}(x)=945\left(\sqrt{1-x^2}\right)^{4}x$} {$P_{5}^{5}(x)=-945\left(\sqrt{1-x^2}\right)^{5}$} P_6 {$P_{6}^{-6}(x)={1\over 46080}\left(\sqrt{1-x^2}\right)^{6}$} {$P_{6}^{-5}(x)={1\over 3840}\left(\sqrt{1-x^2}\right)^{5}x$} {$P_{6}^{-4}(x)={1\over 3840}\left(\sqrt{1-x^2}\right)^{4}(11x^{2}-1)$} {$P_{6}^{-3}(x)={1\over 384}\left(\sqrt{1-x^2}\right)^{3}(11x^{3}-3x)$} {$P_{6}^{-2}(x)={1\over 128}\left(\sqrt{1-x^2}\right)^{2}(33x^{4}-18x^{2}+1)$} {$P_{6}^{-1}(x)={1\over 16}\left(\sqrt{1-x^2}\right)(33x^{5}-30x^{3}+5x)$} {$P_{6}^{0}(x)={1\over 16}(231x^{6}-315x^{4}+105x^{2}-5)$} {$P_{6}^{1}(x)={-21\over 8}\left(\sqrt{1-x^2}\right)(33x^{5}-30x^{3}+5x)$} {$P_{6}^{2}(x)={105\over 8}\left(\sqrt{1-x^2}\right)^{2}(33x^{4}-18x^{2}+1)$} {$P_{6}^{3}(x)={-315\over 2}\left(\sqrt{1-x^2}\right)^{3}(11x^{3}-3x)$} {$P_{6}^{4}(x)={945\over 2}\left(\sqrt{1-x^2}\right)^{4}(11x^{2}-1)$} {$P_{6}^{5}(x)=-10395\left(\sqrt{1-x^2}\right)^{5}x$} {$P_{6}^{6}(x)=10395\left(\sqrt{1-x^2}\right)^{6}$} P_7 {$P_{7}^{-7}(x)={1\over 645120}\left(\sqrt{1-x^2}\right)^{7}$} {$P_{7}^{-6}(x)={1\over 46080}\left(\sqrt{1-x^2}\right)^{6}x$} {$P_{7}^{-5}(x)={1\over 46080}\left(\sqrt{1-x^2}\right)^{5}(13x^{2}-1)$} {$P_{7}^{-4}(x)={1\over 3840}\left(\sqrt{1-x^2}\right)^{4}(13x^{3}-3x)$} {$P_{7}^{-3}(x)={1\over 3840}\left(\sqrt{1-x^2}\right)^{3}(143x^{4}-66x^{2}+3)$} {$P_{7}^{-2}(x)={1\over 384}\left(\sqrt{1-x^2}\right)^{2}(143x^{5}-110x^{3}+15x)$} {$P_{7}^{-1}(x)={1\over 128}\left(\sqrt{1-x^2}\right)(429x^{6}-495x^{4}+135x^{2}-5)$} {$P_{7}^{0}(x)={1\over 16}(429x^{7}-693x^{5}+315x^{3}-35x)$} {$P_{7}^{1}(x)={-7\over 16}\left(\sqrt{1-x^2}\right)(429x^{6}-495x^{4}+135x^{2}-5)$} {$P_{7}^{2}(x)={63\over 8}\left(\sqrt{1-x^2}\right)^{2}(143x^{5}-110x^{3}+15x)$} {$P_{7}^{3}(x)={-315\over 8}\left(\sqrt{1-x^2}\right)^{3}(143x^{4}-66x^{2}+3)$} {$P_{7}^{4}(x)={3465\over 2}\left(\sqrt{1-x^2}\right)^{4}(13x^{3}-3x)$} {$P_{7}^{5}(x)={-10395\over 2}\left(\sqrt{1-x^2}\right)^{5}(13x^{2}-1)$} {$P_{7}^{6}(x)=135135\left(\sqrt{1-x^2}\right)^{6}x$} {$P_{7}^{7}(x)=-135135\left(\sqrt{1-x^2}\right)^{7}$} P_8 {$P_{8}^{-8}(x)={1\over 10321920}\left(\sqrt{1-x^2}\right)^{8}$} {$P_{8}^{-7}(x)={1\over 645120}\left(\sqrt{1-x^2}\right)^{7}x$} {$P_{8}^{-6}(x)={1\over 645120}\left(\sqrt{1-x^2}\right)^{6}(15x^{2}-1)$} {$P_{8}^{-5}(x)={1\over 15360}\left(\sqrt{1-x^2}\right)^{5}(5x^{3}-1x)$} {$P_{8}^{-4}(x)={1\over 15360}\left(\sqrt{1-x^2}\right)^{4}(65x^{4}-26x^{2}+1)$} {$P_{8}^{-3}(x)={1\over 768}\left(\sqrt{1-x^2}\right)^{3}(39x^{5}-26x^{3}+3x)$} {$P_{8}^{-2}(x)={1\over 256}\left(\sqrt{1-x^2}\right)^{2}(143x^{6}-143x^{4}+33x^{2}-1)$} {$P_{8}^{-1}(x)={1\over 128}\left(\sqrt{1-x^2}\right)(715x^{7}-1001x^{5}+385x^{3}-35x)$} {$P_{8}^{0}(x)={1\over 128}(6435x^{8}-12012x^{6}+6930x^{4}-1260x^{2}+35)$} {$P_{8}^{1}(x)={-9\over 16}\left(\sqrt{1-x^2}\right)(715x^{7}-1001x^{5}+385x^{3}-35x)$} {$P_{8}^{2}(x)={315\over 16}\left(\sqrt{1-x^2}\right)^{2}(143x^{6}-143x^{4}+33x^{2}-1)$} {$P_{8}^{3}(x)={-3465\over 8}\left(\sqrt{1-x^2}\right)^{3}(39x^{5}-26x^{3}+3x)$} {$P_{8}^{4}(x)={10395\over 8}\left(\sqrt{1-x^2}\right)^{4}(65x^{4}-26x^{2}+1)$} {$P_{8}^{5}(x)={-135135\over 2}\left(\sqrt{1-x^2}\right)^{5}(5x^{3}-1x)$} {$P_{8}^{6}(x)={135135\over 2}\left(\sqrt{1-x^2}\right)^{6}(15x^{2}-1)$} {$P_{8}^{7}(x)=-2027025\left(\sqrt{1-x^2}\right)^{7}x$} {$P_{8}^{8}(x)=2027025\left(\sqrt{1-x^2}\right)^{8}$} P_9 {$P_{9}^{-9}(x)={1\over 185794560}\left(\sqrt{1-x^2}\right)^{9}$} {$P_{9}^{-8}(x)={1\over 10321920}\left(\sqrt{1-x^2}\right)^{8}x$} {$P_{9}^{-7}(x)={1\over 10321920}\left(\sqrt{1-x^2}\right)^{7}(17x^{2}-1)$} {$P_{9}^{-6}(x)={1\over 645120}\left(\sqrt{1-x^2}\right)^{6}(17x^{3}-3x)$} {$P_{9}^{-5}(x)={1\over 215040}\left(\sqrt{1-x^2}\right)^{5}(85x^{4}-30x^{2}+1)$} {$P_{9}^{-4}(x)={1\over 3072}\left(\sqrt{1-x^2}\right)^{4}(17x^{5}-10x^{3}+1x)$} {$P_{9}^{-3}(x)={1\over 3072}\left(\sqrt{1-x^2}\right)^{3}(221x^{6}-195x^{4}+39x^{2}-1)$} {$P_{9}^{-2}(x)={1\over 256}\left(\sqrt{1-x^2}\right)^{2}(221x^{7}-273x^{5}+91x^{3}-7x)$} {$P_{9}^{-1}(x)={1\over 256}\left(\sqrt{1-x^2}\right)(2431x^{8}-4004x^{6}+2002x^{4}-308x^{2}+7)$} {$P_{9}^{0}(x)={1\over 128}(12155x^{9}-25740x^{7}+18018x^{5}-4620x^{3}+315x)$} {$P_{9}^{1}(x)={-45\over 128}\left(\sqrt{1-x^2}\right)(2431x^{8}-4004x^{6}+2002x^{4}-308x^{2}+7)$} {$P_{9}^{2}(x)={495\over 16}\left(\sqrt{1-x^2}\right)^{2}(221x^{7}-273x^{5}+91x^{3}-7x)$} {$P_{9}^{3}(x)={-3465\over 16}\left(\sqrt{1-x^2}\right)^{3}(221x^{6}-195x^{4}+39x^{2}-1)$} {$P_{9}^{4}(x)={135135\over 8}\left(\sqrt{1-x^2}\right)^{4}(17x^{5}-10x^{3}+1x)$} {$P_{9}^{5}(x)={-135135\over 8}\left(\sqrt{1-x^2}\right)^{5}(85x^{4}-30x^{2}+1)$} {$P_{9}^{6}(x)={675675\over 2}\left(\sqrt{1-x^2}\right)^{6}(17x^{3}-3x)$} {$P_{9}^{7}(x)={-2027025\over 2}\left(\sqrt{1-x^2}\right)^{7}(17x^{2}-1)$} {$P_{9}^{8}(x)=34459425\left(\sqrt{1-x^2}\right)^{8}x$} {$P_{9}^{9}(x)=-34459425\left(\sqrt{1-x^2}\right)^{9}$} P_10 {$P_{10}^{-10}(x)={1\over 3715891200}\left(\sqrt{1-x^2}\right)^{10}$} {$P_{10}^{-9}(x)={1\over 185794560}\left(\sqrt{1-x^2}\right)^{9}x$} {$P_{10}^{-8}(x)={1\over 185794560}\left(\sqrt{1-x^2}\right)^{8}(19x^{2}-1)$} {$P_{10}^{-7}(x)={1\over 10321920}\left(\sqrt{1-x^2}\right)^{7}(19x^{3}-3x)$} {$P_{10}^{-6}(x)={1\over 10321920}\left(\sqrt{1-x^2}\right)^{6}(323x^{4}-102x^{2}+3)$} {$P_{10}^{-5}(x)={1\over 645120}\left(\sqrt{1-x^2}\right)^{5}(323x^{5}-170x^{3}+15x)$} {$P_{10}^{-4}(x)={1\over 43008}\left(\sqrt{1-x^2}\right)^{4}(323x^{6}-255x^{4}+45x^{2}-1)$} {$P_{10}^{-3}(x)={1\over 3072}\left(\sqrt{1-x^2}\right)^{3}(323x^{7}-357x^{5}+105x^{3}-7x)$} {$P_{10}^{-2}(x)={1\over 3072}\left(\sqrt{1-x^2}\right)^{2}(4199x^{8}-6188x^{6}+2730x^{4}-364x^{2}+7)$} {$P_{10}^{-1}(x)={1\over 256}\left(\sqrt{1-x^2}\right)(4199x^{9}-7956x^{7}+4914x^{5}-1092x^{3}+63x)$} {$P_{10}^{0}(x)={1\over 256}(46189x^{10}-109395x^{8}+90090x^{6}-30030x^{4}+3465x^{2}-63)$} {$P_{10}^{1}(x)={-55\over 128}\left(\sqrt{1-x^2}\right)(4199x^{9}-7956x^{7}+4914x^{5}-1092x^{3}+63x)$} {$P_{10}^{2}(x)={495\over 128}\left(\sqrt{1-x^2}\right)^{2}(4199x^{8}-6188x^{6}+2730x^{4}-364x^{2}+7)$} {$P_{10}^{3}(x)={-6435\over 16}\left(\sqrt{1-x^2}\right)^{3}(323x^{7}-357x^{5}+105x^{3}-7x)$} {$P_{10}^{4}(x)={45045\over 16}\left(\sqrt{1-x^2}\right)^{4}(323x^{6}-255x^{4}+45x^{2}-1)$} {$P_{10}^{5}(x)={-135135\over 8}\left(\sqrt{1-x^2}\right)^{5}(323x^{5}-170x^{3}+15x)$} {$P_{10}^{6}(x)={675675\over 8}\left(\sqrt{1-x^2}\right)^{6}(323x^{4}-102x^{2}+3)$} {$P_{10}^{7}(x)={-11486475\over 2}\left(\sqrt{1-x^2}\right)^{7}(19x^{3}-3x)$} {$P_{10}^{8}(x)={34459425\over 2}\left(\sqrt{1-x^2}\right)^{8}(19x^{2}-1)$} {$P_{10}^{9}(x)=-654729075\left(\sqrt{1-x^2}\right)^{9}x$} {$P_{10}^{10}(x)=654729075\left(\sqrt{1-x^2}\right)^{10}$} |