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A105952 (2n)-th Legendre polynomial P_{2n}(x), evaluated at x = 2n-1. Here the Legendre polynomials are normalized so that P_{n}(1) = 1. 1
1, 321, 213445, 278905249, 610897146201, 2023268287369681, 9449986579423765453, 59214605458489033180545, 479530506556330198532943409, 4875296429727384973283863144801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..175

FORMULA

a(n) ~ n^(2*n)*2^(4*n)/(exp(1)*sqrt(2*Pi*n)). - Vaclav Kotesovec, Jul 31 2013

EXAMPLE

P_{4}(x) = 35/8*x^4 - 15/4*x^2 + 3/8; evaluating at x=3 gives 321.

MAPLE

with(orthopoly, P); seq(P(2*n, 2*n-1), n=1..12);

MATHEMATICA

Table[LegendreP[2*n, 2*n-1], {n, 1, 20}] (* Vaclav Kotesovec, Jul 31 2013 *)

PROG

(PARI) a(n)=pollegendre(2*n, 2*n-1) \\ Charles R Greathouse IV, Mar 19 2017

CROSSREFS

Sequence in context: A074350 A144124 A090101 * A062205 A054034 A004947

Adjacent sequences:  A105949 A105950 A105951 * A105953 A105954 A105955

KEYWORD

easy,nonn

AUTHOR

Isabel C. Lugo (izzycat(AT)gmail.com), Apr 27 2005

STATUS

approved

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Last modified May 7 06:57 EDT 2021. Contains 343636 sequences. (Running on oeis4.)