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.

A158753 Triangle T(n, k) = A000032(2*(n-k) + 1), read by rows.

Original entry on oeis.org

1, 4, 1, 11, 4, 1, 29, 11, 4, 1, 76, 29, 11, 4, 1, 199, 76, 29, 11, 4, 1, 521, 199, 76, 29, 11, 4, 1, 1364, 521, 199, 76, 29, 11, 4, 1, 3571, 1364, 521, 199, 76, 29, 11, 4, 1, 9349, 3571, 1364, 521, 199, 76, 29, 11, 4, 1, 24476, 9349, 3571, 1364, 521, 199, 76, 29, 11, 4, 1
Offset: 2

Views

Author

Roger L. Bagula and Gary W. Adamson, Mar 25 2009

Keywords

Examples

			Triangle begins as:
     1;
     4,   1;
    11,   4,   1;
    29,  11,   4,  1;
    76,  29,  11,  4,  1;
   199,  76,  29, 11,  4,  1;
   521, 199,  76, 29, 11,  4,  1;
  1364, 521, 199, 76, 29, 11,  4,  1;
		

References

  • H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973, pp. 159-162.

Crossrefs

Programs

  • Magma
    [Lucas(2*n-2*k+1): k in [2..n], n in [2..16]]; // G. C. Greubel, Dec 06 2021
    
  • Mathematica
    Table[LucasL[2*(n-k) + 1], {n, 2, 16}, {k, 2, n}]//Flatten (* G. C. Greubel, Dec 06 2021 *)
  • Sage
    flatten([[lucas_number2(2*(n-k)+1, 1, -1) for k in (2..n)] for n in (2..16)]) # G. C. Greubel, Dec 06 2021

Formula

T(n, k) = 5*e(n, k), where e(n,k) = (e(n-1, k)*e(n, k-1) + 1)/e(n-1, k-1), and e(n, 0) = GoldenRatio^(n) + GoldenRatio^(-n).
Sum_{k=0..n} T(n, k) = A004146(n-1).
T(n, k) = A000032(2*(n-k) + 1). - G. C. Greubel, Dec 06 2021

Extensions

Edited by G. C. Greubel, Dec 06 2021