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.

A192912 Coefficient of x in the reduction by (x^3 -> x + 1) of the polynomial F(n+1)*x^n, where F(n)=A000045 (Fibonacci sequence).

Original entry on oeis.org

0, 1, 0, 3, 10, 24, 78, 231, 680, 2035, 6052, 18000, 53590, 159471, 474580, 1412397, 4203304, 12509144, 37227624, 110790405, 329715412, 981242533, 2920205614, 8690615136, 25863518300, 76970566973, 229066599960, 681708726543
Offset: 0

Views

Author

Clark Kimberling, Jul 12 2011

Keywords

Comments

See A192911.

Examples

			(See A192911.)
		

Crossrefs

Programs

  • GAP
    a:=[0,1,0,3,10,24];; for n in [7..30] do a[n]:=a[n-1]+4*a[n-2]+ 5*a[n-3]+2*a[n-4]-a[n-5]+a[n-6]; od; a; # G. C. Greubel, Jan 12 2019
  • Magma
    m:=30; R:=PowerSeriesRing(Integers(), m); [0] cat Coefficients(R!( x*(1-x-x^2+2*x^3)/(1-x-4*x^2-5*x^3-2*x^4+x^5-x^6) )); // G. C. Greubel, Jan 12 2019
    
  • Mathematica
    (See A192911.)
    LinearRecurrence[{1,4,5,2,-1,1},{0,1,0,3,10,24},28] (* Ray Chandler, Aug 02 2015 *)
  • PARI
    my(x='x+O('x^30)); concat([0], Vec(x*(1-x-x^2+2*x^3)/(1-x-4*x^2 -5*x^3-2*x^4+x^5-x^6))) \\ G. C. Greubel, Jan 12 2019
    
  • Sage
    (x*(1-x-x^2+2*x^3)/(1-x-4*x^2-5*x^3-2*x^4+x^5-x^6)).series(x, 30).coefficients(x, sparse=False) # G. C. Greubel, Jan 12 2019
    

Formula

(See A192911.)
G.f.: x*(1-x-x^2+2*x^3)/(1-x-4*x^2-5*x^3-2*x^4+x^5-x^6). - R. J. Mathar, May 08 2014

A192913 Coefficient of x^2 in the reduction by (x^3 -> x + 1) of the polynomial F(n+1)*x^n, where F(n)=A000045 (Fibonacci sequence).

Original entry on oeis.org

0, 0, 2, 3, 10, 32, 91, 273, 816, 2420, 7209, 21456, 63842, 190008, 565470, 1682835, 5008192, 14904512, 44356229, 132005445, 392851940, 1169138532, 3479389655, 10354762656, 30816068600, 91709498068, 272930078466, 812247687927
Offset: 0

Views

Author

Clark Kimberling, Jul 12 2011

Keywords

Comments

(See A192911.)

Examples

			(See A192911.)
		

Crossrefs

Programs

  • GAP
    a:=[0,0,2,3,10,32];; for n in [7..30] do a[n]:=a[n-1]+4*a[n-2] +5*a[n-3]+2*a[n-4]-a[n-5]+a[n-6]; od; a; # G. C. Greubel, Jan 12 2019
  • Magma
    m:=30; R:=PowerSeriesRing(Integers(), m); [0,0] cat Coefficients(R!( x^2*(1+x)*(2-x)/(1-x-4*x^2-5*x^3-2*x^4+x^5-x^6) )); // G. C. Greubel, Jan 12 2019
    
  • Mathematica
    (See A192911.)
    LinearRecurrence[{1,4,5,2,-1,1},{0,0,2,3,10,32},28] (* Ray Chandler, Aug 02 2015 *)
  • PARI
    my(x='x+O('x^30)); concat([0,0], Vec(x^2*(1+x)*(2-x)/(1-x-4*x^2 -5*x^3-2*x^4+x^5-x^6))) \\ G. C. Greubel, Jan 12 2019
    
  • Sage
    (x^2*(1+x)*(2-x)/(1-x-4*x^2-5*x^3-2*x^4+x^5-x^6)).series(x, 30).coefficients(x, sparse=False) # G. C. Greubel, Jan 12 2019
    

Formula

(See A192911.)
G.f.: x^2*(1+x)*(2-x) / (1 - x - 4*x^2 - 5*x^3 - 2*x^4 + x^5 - x^6). - R. J. Mathar, May 08 2014
a(n) = a(n-1) + 4*a(n-2) + 5*a(n-3) + 2*a(n-4) - a(n-5) + a(n-6). - Wesley Ivan Hurt, Aug 04 2025
Showing 1-2 of 2 results.