This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A349071 #21 Nov 09 2023 08:54:35
%S A349071 1,2,31,846,32257,1580050,94558751,6686381534,545471324161,
%T A349071 50428155189474,5210183616019999,594949288292777902,
%U A349071 74404881332329766401,10114032809617941274226,1484781814660796486716447,234114571438498509048719550,39459584112457284328544403457
%N A349071 a(n) = T(n, 2*n), where T(n, x) is the Chebyshev polynomial of the first kind.
%H A349071 Seiichi Manyama, <a href="/A349071/b349071.txt">Table of n, a(n) for n = 0..321</a>
%H A349071 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html">Chebyshev Polynomial of the First Kind</a>.
%H A349071 Wikipedia, <a href="https://en.wikipedia.org/wiki/Chebyshev_polynomials">Chebyshev polynomials</a>.
%F A349071 a(n) = cosh(n*arccosh(2*n)).
%F A349071 a(n) = ((2*n + sqrt(4*n^2-1))^n + (2*n - sqrt(4*n^2-1))^n)/2.
%F A349071 a(n) ~ 2^(2*n-1) * n^n.
%t A349071 Table[ChebyshevT[n, 2*n], {n, 0, 20}]
%o A349071 (PARI) a(n) = polchebyshev(n, 1, 2*n); \\ _Michel Marcus_, Nov 07 2021
%o A349071 (Python)
%o A349071 from sympy import chebyshevt
%o A349071 def A349071(n): return chebyshevt(n,n<<1) # _Chai Wah Wu_, Nov 08 2023
%Y A349071 Cf. A053120, A115066, A173129, A349072, A349073.
%K A349071 nonn
%O A349071 0,2
%A A349071 _Vaclav Kotesovec_, Nov 07 2021