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.

A156162 a(n) = 34*a(n-1)-a(n-2)-2312 for n > 2; a(1)=625, a(2)=18769.

Original entry on oeis.org

625, 18769, 635209, 21576025, 732947329, 24898630849, 845820499225, 28732998340489, 976076123075089, 33157855186210225, 1126391000208070249, 38264136151888175929, 1299854238163989909025, 44156779961423768728609
Offset: 1

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Author

Klaus Brockhaus, Feb 09 2009

Keywords

Comments

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

Examples

			a(3) = 34*a(2)-a(1)-2312 = 34*18769-625-2312 = 635209.
		

Crossrefs

Third trisection of A156159.
Cf. A156164 (decimal expansion of (17+12*sqrt(2))).

Programs

  • Mathematica
    RecurrenceTable[{a[1]==625,a[2]==18769,a[n]==34a[n-1]-a[n-2]-2312},a,{n,20}] (* or *) LinearRecurrence[{35,-35,1},{625,18769,635209},20] (* Harvey P. Dale, Sep 29 2016 *)
  • PARI
    {m=14; v=concat([625 ,18769], vector(m-2)); for(n=3, m, v[n]=34*v[n-1]-v[n-2]-2312); v}

Formula

a(n) = (578+(387-182*sqrt(2))*(17+12*sqrt(2))^n+(387+182*sqrt(2))*(17-12*sqrt(2))^n)/8.
G.f.: x*(625-3106*x+169*x^2)/((1-x)*(1-34*x+x^2)).

Extensions

G.f. corrected by Klaus Brockhaus, Sep 23 2009