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.

A034801 Triangle of Fibonomial coefficients (k=2).

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 1, 8, 8, 1, 1, 21, 56, 21, 1, 1, 55, 385, 385, 55, 1, 1, 144, 2640, 6930, 2640, 144, 1, 1, 377, 18096, 124410, 124410, 18096, 377, 1, 1, 987, 124033, 2232594, 5847270, 2232594, 124033, 987, 1, 1, 2584, 850136, 40062659, 274715376, 274715376, 40062659, 850136, 2584, 1
Offset: 0

Views

Author

Keywords

Examples

			Triangle begins as:
  1;
  1,   1;
  1,   3,      1;
  1,   8,      8,       1;
  1,  21,     56,      21,       1;
  1,  55,    385,     385,      55,       1;
  1, 144,   2640,    6930,    2640,     144,      1;
  1, 377,  18096,  124410,  124410,   18096,    377,   1;
  1, 987, 124033, 2232594, 5847270, 2232594, 124033, 987, 1;
		

References

  • A. Brousseau, Fibonacci and Related Number Theoretic Tables. Fibonacci Association, San Jose, CA, 1972, p. 88.

Crossrefs

Cf. A010048.

Programs

  • GAP
    F:= function(n,k,q)
        if n=0 and k=0 then return 1;
        else return Product([1..k], j-> Fibonacci(q*(n-j+1))/Fibonacci(q*j));
        fi;
      end;
    Flat(List([0..10], n-> List([0..n], k-> F(n,k,2) ))); # G. C. Greubel, Nov 13 2019
  • Maple
    A034801 := proc(n,k)
        mul(combinat[fibonacci](2*n-2*j),j=0..k-1) /
        mul(combinat[fibonacci](2*j),j=1..k) ;
    end proc: # R. J. Mathar, Sep 02 2017
  • Mathematica
    F[n_, k_, q_]:= Product[Fibonacci[q*(n-j+1)]/Fibonacci[q*j], {j,k}];
    Table[F[n, k, 2], {n,0,10}, {k,0,n}]//Flatten (* G. C. Greubel, Nov 13 2019 *)
  • PARI
    F(n,k,q) = f=fibonacci; prod(j=1,k, f(q*(n-j+1))/f(q*j)); \\ G. C. Greubel, Nov 13 2019
    
  • Sage
    def F(n,k,q):
        if (n==0 and k==0): return 1
        else: return product(fibonacci(q*(n-j+1))/fibonacci(q*j) for j in (1..k))
    [[F(n,k,2) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Nov 13 2019
    

Formula

Fibonomial coefficients formed from sequence F_3k [ 2, 8, 34, ... ].
T(n, k) = Product_{j=0..k-1} Fibonacci(2*(n-j)) / Product_{j=1..k} Fibonacci(2*j).

Extensions

More terms from James Sellers, Feb 09 2000