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.

A162666 a(n) = 20*a(n-1) - 98*a(n-2) for n > 1; a(0) = 1, a(1) = 10.

Original entry on oeis.org

1, 10, 102, 1060, 11204, 120200, 1306008, 14340560, 158822416, 1771073440, 19856872032, 223572243520, 2525471411264, 28599348360320, 324490768902528, 3687079238739200, 41941489422336256, 477496023050283520
Offset: 0

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Author

Klaus Brockhaus, Jul 20 2009

Keywords

Comments

Binomial transform of A147960. Tenth binomial transform of A077957.

Crossrefs

Programs

  • GAP
    a:=[1,10];; for n in [3..20] do a[n]:=20*a[n-1]-98*a[n-2]; od; a; # G. C. Greubel, Aug 27 2019
  • Magma
    [ n le 2 select 9*n-8 else 20*Self(n-1)-98*Self(n-2): n in [1..18] ];
    
  • Maple
    seq(coeff(series((1-10*x)/(1-20*x+98*x^2), x, n+1), x, n), n = 0..20); # G. C. Greubel, Aug 27 2019
  • Mathematica
    Union[Flatten[NestList[{#[[2]],20#[[2]]-98#[[1]]}&,{1,10},20]]]  (* Harvey P. Dale, Feb 25 2011 *)
    LinearRecurrence[{20,-98}, {1,10}, 20] (* G. C. Greubel, Aug 27 2019 *)
  • PARI
    my(x='x+O('x^20)); Vec((1-10*x)/(1-20*x+98*x^2)) \\ G. C. Greubel, Aug 27 2019
    
  • Sage
    def A162666_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P((1-10*x)/(1-20*x+98*x^2)).list()
    A162666_list(20) # G. C. Greubel, Aug 27 2019
    

Formula

a(n) = ((10+sqrt(2))^n + (10-sqrt(2))^n)/2.
G.f.: (1-10*x)/(1-20*x+98*x^2).
E.g.f.: exp(10*x)*cosh(sqrt(2)*x). - Ilya Gutkovskiy, Aug 11 2017