A334089 a(n) = sqrt(A334088(n)/2^(n-1)).

1, 2, 13, 272, 18281, 3944920, 2732887529, 6077512159232, 43384923739812577, 994156445200670735008, 73125714588602035608260981, 17265651822746410593596262486016, 13085551252412040683513520733767180041, 31834381760532514451976501491991780699626368

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Wikipedia, Chebyshev polynomials

Wikipedia, Resultant

Formula

a(n) ~ exp(2*G*n^2/Pi) / 2^(3*n/2 - 5/8), where G is Catalan's constant A006752. - Vaclav Kotesovec, Apr 14 2020

Mathematica

Table[Resultant[ChebyshevT[2*n, x/2], ChebyshevT[2*n, I*x/2], x]^(1/4) / 2^((n-1)/2), {n, 1, 15}] (* Vaclav Kotesovec, Apr 14 2020 *)

Prog

(PARI) {a(n) = sqrtint(sqrtint(polresultant(polchebyshev(2*n, 1, x/2), polchebyshev(2*n, 1, I*x/2)))/2^(n-1))}

Crossrefs

Cf. A065072, A334088, A340295.

Sequence in context: A134296 A086510 A356493 * A326360 A123113 A126742

Adjacent sequences: A334086 A334087 A334088 * A334090 A334091 A334092

Keyword

nonn

Author

Seiichi Manyama, Apr 14 2020

Status

approved