Coefficients of Legendre polynomials.

Terms

a(0) =5a(1) =35a(2) =1260a(3) =4620a(4) =30030a(5) =90090a(6) =1021020a(7) =2771340a(8) =14549535a(9) =37182145a(10) =1487285800a(11) =3650610600a(12) =17644617900a(13) =42075627300a(14) =396713057400a(15) =925663800600