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A318184
a(n) = 2^(n * (n - 1)/2) * 3^((n - 1) * (n - 2)) * n^(n - 3).
5
1, 1, 72, 186624, 13604889600, 24679069470425088, 1036715783690392172494848, 962459606796748852884396910313472, 19112837387997044228759204010262201783812096, 7926475921550134182551017087135940323782552453120000000, 67406870957147550175650545441605700298239194363455522532832462241792
OFFSET
1,3
COMMENTS
Discriminant of Fermat polynomials.
F(0)=0, F(1)=1 and F(n) = 3x F(n - 1) -2 F(n - 2) if n>1.
LINKS
Rigoberto Flórez, Robinson Higuita, and Alexander Ramírez, The resultant, the discriminant, and the derivative of generalized Fibonacci polynomials, arXiv:1808.01264 [math.NT], 2018.
Eric Weisstein's World of Mathematics, Discriminant
Eric Weisstein's World of Mathematics, Fermat Polynomial
MAPLE
seq(2^(n*(n-1)/2)*3^((n-1)*(n-2))*n^(n-3), n=1..12); # Muniru A Asiru, Dec 07 2018
MATHEMATICA
F[0] = 0; F[1] = 1; F[n_] := F[n] = 3 x F[n - 1] - 2 F[n - 2];
a[n_] := Discriminant[F[n], x];
Array[a, 11] (* Jean-François Alcover, Dec 07 2018 *)
PROG
(PARI) a(n) = 2^(n*(n-1)/2) * 3^((n-1)*(n-2)) * n^(n-3); \\ Michel Marcus, Dec 07 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Rigoberto Florez, Aug 20 2018
STATUS
approved