cp's OEIS Frontend

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.

A303826 Hankel transform of A001246.

Original entry on oeis.org

1, 3, 99, 43881, 280974025, 26916213134875, 39339805703866118875, 887919033897631593738548625, 311967217568836709207331125906048625, 1715750319988362944273302140220635494624999475
Offset: 0

Views

Author

Karol A. Penson, May 01 2018

Keywords

Comments

a(n) is the determinant of the (n+1) X (n+1) matrix A defined by A[i,j] = A001246(i+j-2) for 1 <= i,j <= n+1. - Altug Alkan, May 01 2018

Examples

			a(2) = 99 because determinant of the following matrix is 99.
[1  1   4]
[1  4  25]
[4 25 196]
		

Crossrefs

Programs

  • Maple
    a:= n-> LinearAlgebra[Determinant](Matrix(n+1, (i, j)->
            (t-> (binomial(2*t, t)/(t+1))^2)(i+j-2))):
    seq(a(n), n=0..15);  # Alois P. Heinz, May 01 2018
  • Mathematica
    Table[Det[
      Table[(CatalanNumber[i + j - 2])^2, {i, 1, n + 1}, {j, 1, n + 1}]], {n,
      0, 10}]
  • PARI
    a(n) = matdet(matrix(n+1, n+1, i, j, (binomial(2*(i+j-2),(i+j-2))/(i+j-1))^2)); \\ Altug Alkan, May 01 2018

Formula

a(n)^(1/n) ~ d * 4^n, where d = 0.263565... - Vaclav Kotesovec, May 06 2024

Extensions

Name simplified by Andrey Zabolotskiy, May 02 2018