%I A001800 M3123 N1266
%S A001800 1,3,30,70,315,693,12012,25740,109395,230945,1939938,4056234,16900975,
%T A001800 35102025,1163381400,2404321560,9917826435,20419054425,167890003050,
%U A001800 344616322050,1412926920405,2893136075115,47342226683700
%N A001800 Coefficients of Legendre polynomials.
%D A001800 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001800 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001800 M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, 
               National Bureau of Standards Applied Math. Series 55, 1964 (and various 
               reprintings), p. 798.
%D A001800 G. Pr\'{e}vost, Tables de Fonctions Sph\'{e}riques. Gauthier-Villars, 
               Paris, 1933, pp. 156-157.
%H A001800 M. Abramowitz and I. A. Stegun, eds., <a href="http://www.nrbook.com/
               abramowitz_and_stegun/">Handbook of Mathematical Functions</a>, National 
               Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 
               [alternative scanned copy].
%H A001800 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               LegendrePolynomial.html">MathWorld page</a>, eq. 28.
%F A001800 (n+1) * C(2n+2, n+1) / 2^[A000120(n+2)].
%o A001800 (PARI) a(n)=if(n<0,0,-polcoeff(pollegendre(n),n-2)*2^valuation((n\2*2)!,
               2))
%Y A001800 Cf. A001790, A001801, A008316.
%Y A001800 Cf. A001803.
%Y A001800 Diagonal 2 of triangle A100258.
%Y A001800 Sequence in context: A061472 A132084 A012009 this_sequence A152767 A035328 
               A100259
%Y A001800 Adjacent sequences: A001797 A001798 A001799 this_sequence A001801 A001802 
               A001803
%K A001800 nonn
%O A001800 0,2
%A A001800 N. J. A. Sloane (njas(AT)research.att.com).
%E A001800 More terms from Michael Somos, Oct 25, 2002