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Numerator of the discriminant of the n-th Legendre polynomial.
1

%I #7 Mar 04 2023 08:58:22

%S 1,3,135,23625,260465625,11371668721875,7888446990683634375,

%T 21776965089186101310140625,15330043202319289712414934678515625,

%U 43033523436556282747812223470803609794921875,1927983533652930855481078826533672813447199742802734375

%N Numerator of the discriminant of the n-th Legendre polynomial.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/LegendrePolynomial.html">Legendre Polynomial</a>.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PolynomialDiscriminant.html">Polynomial Discriminant</a>.

%t a[n_] := Numerator[Discriminant[LegendreP[n, x], x]]; Array[a, 11] (* _Amiram Eldar_, Mar 04 2023 *)

%o (PARI) a(n) = numerator(poldisc(pollegendre(n)));

%Y Cf. A361196 (denominators).

%K nonn,frac

%O 1,2

%A _Michel Marcus_, Mar 04 2023