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.

A162669 a(n) = n*(n+1)*(n+2)*(n+3)*(n+4)*(n+5)/5.

Original entry on oeis.org

0, 144, 1008, 4032, 12096, 30240, 66528, 133056, 247104, 432432, 720720, 1153152, 1782144, 2673216, 3907008, 5581440, 7814016, 10744272, 14536368, 19381824, 25502400, 33153120, 42625440, 54250560, 68402880, 85503600, 106024464, 130491648, 159489792, 193666176
Offset: 0

Views

Author

Vincenzo Librandi, Jul 10 2009

Keywords

Crossrefs

Cf. A000579.

Programs

  • GAP
    List([0..30], n-> 144*Binomial(n+5, 6)); # G. C. Greubel, Aug 27 2019
  • Magma
    [n*(n+1)*(n+2)*(n+3)*(n+4)*(n+5)/5: n in [1..30]]; // Vincenzo Librandi, Mar 05 2012
    
  • Maple
    seq(144*binomial(n+5,6), n = 0..30); # G. C. Greubel, Aug 27 2019
  • Mathematica
    CoefficientList[Series[144*x/(1-x)^7,{x,0,30}],x] (* Vincenzo Librandi, Mar 05 2012 *)
    Table[(Times@@(n+Range[0,5]))/5,{n,0,30}] (* Harvey P. Dale, Jul 01 2019 *)
    144*Binomial[Range[30] +4, 6] (* G. C. Greubel, Aug 27 2019 *)
  • PARI
    vector(30, n, 144*binomial(n+4,6)) \\ G. C. Greubel, Aug 27 2019
    
  • Sage
    [144*binomial(n+5,6) for n in (0..30)] # G. C. Greubel, Aug 27 2019
    

Formula

From R. J. Mathar, Jul 13 2009: (Start)
a(n) = 144 * A000579(n+5).
G.f.: 144*x/(1-x)^7. (End)
E.g.f.: x*(720 +1800*x +1200*x^2 +300*x^3 +30*x^4 +x^5)*exp(x)/5. - G. C. Greubel, Aug 27 2019
From Amiram Eldar, Jan 09 2022: (Start)
Sum_{n>=1} 1/a(n) = 1/120.
Sum_{n>=1} (-1)^(n+1)/a(n) = 4*log(2)/3 - 661/720. (End)

Extensions

Definition factorized, offset corrected by R. J. Mathar, Jul 13 2009