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.

Showing 1-2 of 2 results.

A128585 Triangle read by rows: A007318^(-1) * A128541.

Original entry on oeis.org

1, 0, 1, -1, -1, 2, 2, 0, -4, 3, -3, 2, 4, -9, 5, 4, -5, 0, 15, -20, 8, -5, 9, -10, -15, 45, -40, 13, 6, -14, 28, 0, -70, 112, -78, 21, -7, 20, -56, 42, 70, -224, 260, -147, 34, 8, -27, 96, -126, 0, 336, -624, 567, -272, 55, -9, 35, -150, 270, -210, -336, 1170, -1575, 1190, -495, 89
Offset: 1

Views

Author

Gary W. Adamson, Mar 11 2007

Keywords

Comments

Row sums = A039834: (1, 1, 0, -1, 2, -3, 5, -8, ...); binomial transform of A039834 = (1, 2, 3, 5, 8, 13, 21, ...).

Examples

			First few rows of the triangle
   1;
   0,   1;
  -1,  -1,   2;
   2,   0,  -4,   3;
  -3,   2,   4,  -9,   5;
   4,  -5,   0,  15, -20,   8;
  ...
		

Crossrefs

Formula

Inverse binomial transform of A128541.
Matrix product A130595 * A128541. - Georg Fischer, Jun 01 2023

Extensions

a(35) corrected and more terms from Georg Fischer, Jun 01 2023

A128540 Triangle A127647 * A097806, read by rows.

Original entry on oeis.org

1, 1, 1, 0, 2, 2, 0, 0, 3, 3, 0, 0, 0, 5, 5, 0, 0, 0, 0, 8, 8, 0, 0, 0, 0, 0, 13, 13, 0, 0, 0, 0, 0, 0, 21, 21, 0, 0, 0, 0, 0, 0, 0, 34, 34, 0, 0, 0, 0, 0, 0, 0, 0, 55, 55, 0, 0, 0, 0, 0, 0, 0, 0, 0, 89, 89, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 144, 144
Offset: 1

Views

Author

Gary W. Adamson, Mar 10 2007

Keywords

Comments

Row sums = A094895 starting (1, 2, 4, 6, 10, 16, 26, ...). A128541 = A097806 * A127647.

Examples

			First few rows of the triangle:
  1;
  1, 1;
  0, 2, 2;
  0, 0, 3, 3;
  0, 0, 0, 5, 5;
  0, 0, 0, 0, 8, 8;
  ...
		

Crossrefs

Programs

  • Magma
    [k eq n select Fibonacci(n) else k eq n-1 select Fibonacci(n) else 0: k in [1..n], n in [1..15]]; // G. C. Greubel, Jul 11 2019
    
  • Mathematica
    Table[If[k==n || k==n-1, Fibonacci[n], 0], {n, 15}, {k, n}]//Flatten (* G. C. Greubel, Jul 11 2019 *)
  • PARI
    T(n,k) = if(k==n || k==n-1, fibonacci(n), 0); \\ G. C. Greubel, Jul 11 2019
    
  • Sage
    def T(n, k):
        if (k==n): return fibonacci(n)
        elif (k==n-1): return fibonacci(n)
        else: return 0
    [[T(n, k) for k in (1..n)] for n in (1..15)] # G. C. Greubel, Jul 11 2019

Formula

A127646 * A097806 as infinite lower triangular matrices.
Showing 1-2 of 2 results.