OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..296
Wikipedia, Chebyshev polynomials.
FORMULA
a(n) = Sum_{k=0..n} binomial(2*n, 2*k)*(2*n+1)^(n-k)*(2*n)^k.
a(n) = A322790(2*n, n).
a(n) = T_{n}(4*n+1) where T_{n}(x) is a Chebyshev polynomial of the first kind.
a(n) ~ exp(1/4) * 2^(3*n - 1) * n^n. - Vaclav Kotesovec, Dec 25 2018
PROG
(PARI) {a(n) = sum(k=0, n, binomial(2*n, 2*k)*(2*n+1)^(n-k)*(2*n)^k)}
(PARI) {a(n) = polchebyshev(n, 1, 4*n+1)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Dec 25 2018
STATUS
approved