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.

A099483 A Fibonacci convolution.

Original entry on oeis.org

0, 1, 3, 7, 18, 48, 126, 329, 861, 2255, 5904, 15456, 40464, 105937, 277347, 726103, 1900962, 4976784, 13029390, 34111385, 89304765, 233802911, 612103968, 1602508992, 4195423008, 10983760033, 28755857091, 75283811239, 197095576626
Offset: 0

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Author

Paul Barry, Oct 18 2004

Keywords

Comments

A Chebyshev transform of the sequence 0,1,3,9,27 with g.f. x/(1-3x). The image of G(x) under the Chebyshev transform is (1/(1+x^2))G(x/(1+x^2)).

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{3,-2,3,-1},{0,1,3,7},30] (* Harvey P. Dale, May 23 2016 *)

Formula

G.f.: x/((1+x^2)(1-3x+x^2)); a(n)=3a(n-1)-2a(n-2)+3a(n-3); a(n)=sum{k=0..n, cos(pi*k/2)F(2(n-k))}. a(n)=sum{k=0..floor(n/2), binomial(n-k, k)(-1)^n*(3^(n-2k)-0^(n-2k))/3}.
(1/6) [2Fib(2n+2) - I^n - (-I)^n ]. - Ralf Stephan, Dec 04 2004

A099484 A Fibonacci convolution.

Original entry on oeis.org

1, 1, 2, 7, 19, 48, 125, 329, 862, 2255, 5903, 15456, 40465, 105937, 277346, 726103, 1900963, 4976784, 13029389, 34111385, 89304766, 233802911, 612103967, 1602508992, 4195423009, 10983760033, 28755857090, 75283811239, 197095576627
Offset: 0

Views

Author

Paul Barry, Oct 18 2004

Keywords

Comments

A Chebyshev transform of the sequence 1,1,3,9,27 with g.f. (1-2x)/(1-3x). The image of G(x) under the Chebyshev transform is (1/(1+x^2))G(x/(1+x^2)).

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{3,-2,3,-1},{1,1,2,7},40] (* Harvey P. Dale, Mar 25 2020 *)

Formula

G.f.: (1-x)^2/((1+x^2)*(1-3*x+x^2)), convolution of A176742 and A001906.
a(n)=3a(n-1)-2a(n-2)+3a(n-3);
a(n)=sum{k=0..floor(n/2), binomial(n-k, k)(-1)^n*(3^(n-2k)+2*0^(n-2k))/3};
a(n)=sum{k=0..n, (0^k-2sin(pi*k/2))F(2(n-k)+2)}.
(1/3) [Fib(2n+2) + I^n + (-I)^n ]. - Ralf Stephan, Dec 04 2004
3*a(n) = A001906(n+1) +2*A056594(n). - R. J. Mathar, Jun 17 2020
Showing 1-2 of 2 results.