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.

A166168 G.f.: exp( Sum_{n>=1} Lucas(n^2)*x^n/n ) where Lucas(n) = A000204(n).

Original entry on oeis.org

1, 1, 4, 29, 585, 34212, 5600397, 2490542953, 2968152042068, 9416588994339205, 79216509536543420965, 1762508872870620792746360, 103525263562786817866762466405, 16031370626878431551103688398524485
Offset: 0

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Author

Paul D. Hanna, Oct 08 2009

Keywords

Comments

Conjectured to consist entirely of integers.
The Lucas numbers (A000204) forms the logarithmic derivative of the Fibonacci numbers (A000045).
Note that Lucas(n^2) = [(1+sqrt(5))/2]^(n^2) + [(1-sqrt(5))/2]^(n^2).

Examples

			G.f.: A(x) = 1 + x + 4*x^2 + 29*x^3 + 585*x^4 + 34212*x^5 +...
log(A(x)) = x + 7*x^2/2 + 76*x^3/3 + 2207*x^4/4 + 167761*x^5/5 + 33385282*x^6/6 +...+ Lucas(n^2)*x^n/n +...
		

Crossrefs

Programs

  • Maple
    with(combinat): seq(coeff(series(exp(add((fibonacci(k^2-1)+fibonacci(k^2+1))*x^k/k,k=1..n)),x,n+1), x, n), n = 0 .. 15); # Muniru A Asiru, Dec 18 2018
  • Mathematica
    CoefficientList[Series[Exp[Sum[LucasL[n^2]*x^n/n, {n, 1, 200}]], {x, 0, 50}], x](* G. C. Greubel, May 06 2016 *)
  • PARI
    {a(n)=polcoeff(exp(sum(m=1,n,(fibonacci(m^2-1)+fibonacci(m^2+1))*x^m/m)+x*O(x^n)),n)}

Formula

a(n) = (1/n)*Sum_{k=1..n} Lucas(k^2)*a(n-k), a(0)=1.
Logarithmic derivative yields A166169.

A214221 (n^3)-th Lucas number (beginning at 2).

Original entry on oeis.org

2, 1, 47, 439204, 23725150497407, 132878596168524201724674011, 1384619022984618483717737087933569992335566082, 481682208844384447843365760878364816732549453120338354329505085763436029
Offset: 0

Views

Author

Jonathan Vos Post, Jul 07 2012

Keywords

Comments

This is to A182149 (n^3)-th Fibonacci number, as A000032 is to A000045.

Examples

			a(2) = L(2^3) = L(8) = 47.
		

Crossrefs

Programs

  • Maple
    a:= n-> (<<0|1>, <1|1>>^(n^3). <<2, 1>>)[1, 1]:
    seq (a(n), n=0..7);  # Alois P. Heinz, Jul 07 2012
  • Mathematica
    f[n_] := LucasL[n^3]; Array[f, 8, 0] (* Robert G. Wilson v, Jul 07 2012 *)

Formula

a(n) = A000032(A000578(n)).
a(n) = term (1,1) in the 2 X 1 matrix [0,1; 1,1]^(n^3) * [2;1]. - Alois P. Heinz, Jul 07 2012
Showing 1-2 of 2 results.