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 1-3 of 3 results.

A156573 a(n) = 34*a(n-1) - a(n-2) - 4232 for n > 2; a(1)=529, a(2)=13225.

Original entry on oeis.org

529, 13225, 444889, 15108769, 513249025, 17435353849, 592288777609, 20120383080625, 683500735959409, 23218904639535049, 788759257008228025, 26794595833640213569, 910227499086759029089, 30920940373116166771225
Offset: 1

Views

Author

Klaus Brockhaus, Feb 11 2009

Keywords

Examples

			a(3) = 34*a(2) - a(1) - 4232 = 34*13225 - 529 - 4232 = 444889.
		

Crossrefs

Second trisection of A156572.
Cf. A008844, A156164 (decimal expansion of 17+12*sqrt(2)), A156574, A156575.

Programs

  • Mathematica
    LinearRecurrence[{35,-35,1}, {529,13225,444889}, 30] (* G. C. Greubel, Jan 04 2022 *)
  • PARI
    {m=14; v=concat([529, 13225], vector(m-2)); for(n=3, m, v[n]=34*v[n-1]-v[n-2]-4232); v}
    
  • Sage
    def a(n): return -529*bool(n==0) + (529/4) + (3/4)*(chebyshev_U(n, 17) - 33*chebyshev_U(n-1, 17))
    [a(n) for n in (1..30)] # G. C. Greubel, Jan 04 2022

Formula

a(n) = 529*(2 + (3 - 2*sqrt(2))*(17 + 12*sqrt(2))^n + (3 + 2*sqrt(2))*(17 - 12*sqrt(2))^n)/8.
a(n) = 529*A008844(n).
G.f.: 529*x*(1 -10*x +x^2)/((1-x)*(1-34*x+x^2)). [corrected by Klaus Brockhaus, Sep 22 2009]
Limit_{n -> infinity} a(n)/a(n-1) = 17+12*sqrt(2).
a(n) = -529*[n=0] + (529/4) + (1587/4)*(ChebyshevU(n, 17) - 33*ChebyshevU(n-1, 17)). - G. C. Greubel, Jan 04 2022

Extensions

Revised by Klaus Brockhaus, Feb 16 2009

A156574 a(n) = 34*a(n-1) - a(n-2) - 4232 for n > 2; a(1)=1369, a(2)=42025.

Original entry on oeis.org

1369, 42025, 1423249, 48344209, 1642275625, 55789022809, 1895184495649, 64380483825025, 2187041265550969, 74295022544903689, 2523843725261170225, 85736391636334879729, 2912513471910124736329, 98939721653307906151225
Offset: 1

Views

Author

Klaus Brockhaus, Feb 11 2009

Keywords

Comments

lim_{n -> infinity} a(n)/a(n-1) = 17+12*sqrt(2).

Examples

			a(3) = 34*a(2) - a(1) - 4232 = 34*42025 - 1369 - 4232 = 1423249.
		

Crossrefs

Third trisection of A156572.
Cf. A156164 (decimal expansion of 17+12*sqrt(2)), A156573, A156575.

Programs

  • Mathematica
    LinearRecurrence[{35,-35,1}, {1369, 42025, 1423249}, 30] (* G. C. Greubel, Jan 04 2022 *)
  • PARI
    {m=14; v=concat([1369, 42025], vector(m-2)); for(n=3, m, v[n]=34*v[n-1]-v[n-2]-4232); v}
    
  • Sage
    def a(n): return -289*bool(n==0) + (529/4) + (3/4)*(209*chebyshev_U(n, 17) - 5457*chebyshev_U(n-1, 17))
    [a(n) for n in (1..30)] # G. C. Greubel, Jan 04 2022

Formula

a(n) = (1058 + (627 - 238*sqrt(2))*(17 + 12*sqrt(2))^n + (627 + 238*sqrt(2))*(17 - 12*sqrt(2))^n)/8.
G.f.: x*(1369 -5890*x +289*x^2)/((1-x)*(1-34*x+x^2)).
a(n) = -289*[n=0] + (529/4) + (3/4)*(209*ChebyshevU(n, 17) - 5457*ChebyshevU(n - 1, 17)). - G. C. Greubel, Jan 04 2022

Extensions

Revised by Klaus Brockhaus, Feb 16 2009
G.f. corrected by Klaus Brockhaus, Sep 22 2009

A156575 a(n) = 34*a(n-1)-a(n-2)-4232 for n > 2; a(1)=289, a(2)=4225.

Original entry on oeis.org

289, 4225, 139129, 4721929, 160402225, 5448949489, 185103876169, 6288082836025, 213609712544449, 7256442143671009, 246505423172265625, 8373927945713356009, 284467044731081834449, 9663505592911069011025
Offset: 1

Views

Author

Klaus Brockhaus, Feb 11 2009

Keywords

Comments

lim_{n -> infinity} a(n)/a(n-1) = 17+12*sqrt(2).

Examples

			a(4) = 34*a(3) -a(2) -4232 = 34*139129 -4225 -4232 = 4721929.
		

Crossrefs

First trisection of A156572.
Cf. A156164 (decimal expansion of 17+12*sqrt(2)), A156573, A156574.

Programs

  • Mathematica
    RecurrenceTable[{a[1]==289,a[2]==4225,a[n]==34a[n-1]-a[n-2]-4232},a,{n,20}] (* or *) LinearRecurrence[{35,-35,1},{289,4225,139129},20] (* Harvey P. Dale, Dec 15 2011 *)
  • PARI
    {m=14; v=concat([289, 4225], vector(m-2)); for(n=3, m, v[n]=34*v[n-1]-v[n-2]-4232); v}
    
  • Sage
    def a(n): return -1369*bool(n==0) + (529/4) + (3/4)*(1649*chebyshev_U(n, 17) - 55857*chebyshev_U(n-1, 17))
    [a(n) for n in (1..30)] # G. C. Greubel, Jan 04 2022

Formula

a(n) = (1058 + (4947 - 3478*sqrt(2))*(17 + 12*sqrt(2))^n + (4947 + 3478*sqrt(2))*(17 - 12*sqrt(2))^n)/8.
G.f.: x*(289 -5890*x +1369*x^2)/((1-x)*(1-34*x+x^2)).
a(1)=289, a(2)=4225, a(3)=139129, a(n) = 35*a(n-1) - 35*a(n-2) + a(n-3). - Harvey P. Dale, Dec 15 2011
a(n) = -1369*[n=0] + (529/4) + (3/4)*(1649*ChebyshevU(n, 17) - 55857*ChebyshevU(n-1, 17)). - G. C. Greubel, Jan 04 2022

Extensions

Revised by Klaus Brockhaus, Feb 16 2009
G.f. corrected by Klaus Brockhaus, Sep 22 2009
Showing 1-3 of 3 results.