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.

A168308 The fifth left hand column of triangle A167591.

Original entry on oeis.org

525, 12396, 162740, 1537216, 11589216, 73898880, 413745024, 2087500800, 9672309504, 41745859584, 169680276480, 655126331392, 2419298385920, 8593269522432, 29494166618112, 98195558891520, 318148898783232, 1005877391523840, 3110695891894272
Offset: 5

Views

Author

Johannes W. Meijer, Nov 23 2009

Keywords

Crossrefs

Equals the fifth left hand column of triangle A167591.
Other left hand columns are A001787, A167592, A167593 and A168307.

Programs

  • Magma
    [2^n*(107*n^9-1824*n^8+14124*n^7-62538*n^6+ 165228*n^5-259476*n^4+241561*n^3-133542*n^2+ 36360*n)/241920: n in [5..30]]; // Vincenzo Librandi, Jul 18 2016
  • Mathematica
    LinearRecurrence[{20,-180,960,-3360,8064,-13440,15360,-11520,5120,-1024},{525, 12396, 162740, 1537216, 11589216, 73898880, 413745024, 2087500800, 9672309504, 41745859584}, 50] (* G. C. Greubel, Jul 17 2016 *)

Formula

a(n) = 2^n*(107*n^9 - 1824*n^8 + 14124*n^7 - 62538*n^6 + 165228*n^5 - 259476*n^4 + 241561*n^3 - 133542*n^2 + 36360*n)/241920.
G.f.: (1936*z^4 + 9696*z^3 + 9320*z^2 + 1896*z + 525)/(1-2*z)^10.
a(n) = 20*a(n-1) - 180*a(n-2) + 960*a(n-3) - 3360*a(n-4) + 8064*a(n-5) - 13440*a(n-6) + 15360*a(n-7) - 11520*a(n-8) + 5120*a(n-9) - 1024*a(n-10).
a(n) - 19*a(n-1) + 162*a(n-2) - 816*a(n-3) + 2688*a(n-4) - 6048*a(n-5) + 9408*a(n-6) -9984*a(n-7) + 6912*a(n-8) - 2816*a(n-9) + 512*a(n-10) = 321*2^(n-2).