A002461 Coefficients of Legendre polynomials.

1, 3, 20, 35, 126, 231, 3432, 6435, 24310, 46189, 352716, 676039, 2600150, 5014575, 155117520, 300540195, 1166803110, 2268783825, 17672631900, 34461632205, 134564468610, 263012370465, 4116715363800, 8061900920775, 31602651609438, 61989816618513, 486734856412028

Offset: 2

Author

N. J. A. Sloane

Keywords

• nonn

References

• A. Fletcher, J. C. P. Miller, L. Rosenhead and L. J. Comrie, An Index of Mathematical Tables. Vols. 1 and 2, 2nd ed., Blackwell, Oxford and Addison-Wesley, Reading, MA, 1962, Vol. 1, p. 362.
• G. Prévost, Tables de Fonctions Sphériques. Gauthier-Villars, Paris, 1933, pp. 156-157.
• N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Programs

PARI

a(n) = if (n==2, 1, n*abs(numerator((1/(1-2*n))*binomial(2*n,n)/(4^n)))); \\ Michel Marcus, Feb 02 2015

Formula

1 if n=2, n * |A002596(n)| else. - Ralf Stephan, Sep 01 2003

Extensions

More terms from Michel Marcus, Feb 02 2015