A128540 Triangle A127647 * A097806, read by rows.

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

1,5

Comments

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

Links

G. C. Greubel, Rows n = 1..100 of triangle, flattened

Formula

A127646 * A097806 as infinite lower triangular matrices.

Example

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;
  ...

Mathematica

Table[If[k==n || k==n-1, Fibonacci[n], 0]], {n, 15}, {k, n}]//Flatten (* G. C. Greubel, Jul 11 2019 *)

Prog

(PARI) T(n, k) = if(k==n || k==n-1, fibonacci(n), 0); \\ G. C. Greubel, Jul 11 2019
(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
(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

Crossrefs

Cf. A127647, A097806, A128541.

Sequence in context: A325820 A109042 A322403 * A160692 A051775 A108036

Adjacent sequences: A128537 A128538 A128539 * A128541 A128542 A128543

Keyword

nonn,tabl

Author

Gary W. Adamson, Mar 10 2007

Status

approved