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.

A182824 Inverse of coefficient array for orthogonal polynomials p(n,x)=(x-(2n-1))*p(n-1,x)-(2n-2)^2*p(n-2,x).

Original entry on oeis.org

1, 1, 1, 5, 4, 1, 21, 33, 9, 1, 153, 264, 114, 16, 1, 1209, 2769, 1410, 290, 25, 1, 12285, 32076, 20259, 5040, 615, 36, 1, 140589, 432657, 314811, 94899, 14175, 1155, 49, 1, 1871217, 6475536, 5423076, 1886304, 337974, 33936, 1988, 64, 1, 27773361, 108067041, 101497860, 40257540, 8321670, 997542, 72324, 3204, 81, 1, 460041525, 1975940244, 2064827781, 915887520, 214906770, 29709288, 2565738, 141120, 4905, 100, 1
Offset: 0

Views

Author

Paul Barry, Dec 05 2010

Keywords

Comments

Inverse is the coefficient array for the orthogonal polynomials p(0,x)=1,p(1,x)=x-1,p(n,x)=(x-(2n-1))*p(n-1,x)-(2n-2)^2*p(n-2,x).
Inverse is A182826. First column is A182825.

Examples

			Triangle begins:
  1,
  1, 1,
  5, 4, 1,
  21, 33, 9, 1,
  153, 264, 114, 16, 1,
  1209, 2769, 1410, 290, 25, 1,
  12285, 32076, 20259, 5040, 615, 36, 1,
  140589, 432657, 314811, 94899, 14175, 1155, 49, 1,
  1871217, 6475536, 5423076, 1886304, 337974, 33936, 1988, 64, 1
Production matrix begins:
  1, 1,
  4, 3, 1,
  0, 16, 5, 1,
  0, 0, 36, 7, 1,
  0, 0, 0, 64, 9, 1,
  0, 0, 0, 0, 100, 11, 1,
  0, 0, 0, 0, 0, 144, 13, 1,
  0, 0, 0, 0, 0, 0, 196, 15, 1,
  0, 0, 0, 0, 0, 0, 0, 256, 17, 1
  0, 0, 0, 0, 0, 0, 0, 0, 324, 19, 1
		

Programs

  • Mathematica
    (* The function RiordanArray is defined in A256893. *)
    RiordanArray[1/(Cos[Sqrt[3]*#] - Sin[Sqrt[3]*#]/Sqrt[3])&, Sin[Sqrt[3]*#]/ (Sqrt[3]*Cos[Sqrt[3]*#] - Sin[Sqrt[3]*#])&, 11, True] // Flatten (* Jean-François Alcover, Jul 19 2019 *)

Formula

Exponential Riordan array [1/(cos(sqrt(3)*x)-sin(sqrt(3)*x)/sqrt(3)), sin(sqrt(3)*x)/(sqrt(3)*cos(sqrt(3)*x)-sin(sqrt(3)*x))].