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.

User: Mark Sapir

Mark Sapir's wiki page.

Mark Sapir has authored 1 sequences.

A192081 Wronskian of sin(k*x) and cos(k*x), k=1,...,n.

Original entry on oeis.org

1, 1, 18, 86400, 548674560000, 14450101093977292800000, 3837346984091658732083085312000000000, 21256593329287301582222798129123366786826240000000000000, 4543629380532096097361509541360459283717770305881596724510720000000000000000000
Offset: 0

Author

Mark Sapir, Oct 11 2011

Keywords

Comments

a(n) is the Wronskian of functions {cos(x), sin(x), cos(2x), sin(2x), ..., cos(n*x), sin(n*x)}.

Examples

			a(3) = (1*6*120)^2/6 = 86400.
		

Programs

  • Maple
    a:= n-> mul((2*i-1)!, i=1..n)^2/n!:
    seq(a(n), n=0..8);  # Alois P. Heinz, Aug 02 2023
  • Mathematica
    s = 1; Join[{s}, Table[s=s*((2*n-1)!)^2/n, {n, 2, 7}]] (* T. D. Noe, Oct 11 2011 *)

Formula

a(n) = (1! * 3! * ... * (2n-1)!)^2/n!.

Extensions

a(0)=1 prepended by Alois P. Heinz, Aug 02 2023