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 1-2 of 2 results.

A089932 G.f.: (1-x)^5/((-1+4*x-3*x^2+x^3)*(1-3*x+x^2)*(-1+2*x)).

Original entry on oeis.org

1, 4, 16, 60, 215, 747, 2539, 8491, 28049, 91782, 298109, 962594, 3093687, 9905444, 31619072, 100681587, 319944693, 1015039586, 3215903436, 10177462312, 32179381609, 101668695088, 321014982282, 1013068488800, 3195703133266, 10077204123667, 31767718475161
Offset: 0

Views

Author

N. J. A. Sloane, Jan 18 2004

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(1-x)^5/((-1+4x-3x^2+x^3)(1-3x+x^2)(-1+2x)),{x,0,30}],x] (* or *) LinearRecurrence[{9,-30,46,-34,13,-2},{1,4,16,60,215,747},30] (* Harvey P. Dale, May 20 2015 *)

A089947 G.f.: (1-x)^9/((1-5*x+6*x^2-4*x^3+x^4)*(-1+4*x-3*x^2+x^3)*(1-3*x+x^2)*(-1+2*x)).

Original entry on oeis.org

1, 5, 25, 115, 500, 2092, 8512, 33910, 132892, 514079, 1968021, 7470434, 28160354, 105542777, 393672627, 1462503264, 5414896000, 19991387639, 73628208598, 270614786791, 992880076249, 3637400475618, 13308475404934, 48639360355243, 177597694845849
Offset: 0

Views

Author

N. J. A. Sloane, Jan 18 2004

Keywords

References

  • A. Burstein and T. Mansour, Words restricted by 3-letter ..., Annals. Combin., 7 (2003), 1-14; see Th. 3.6, case k=5.

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(1-x)^9/((1-5x+6x^2-4x^3+x^4)(-1+4x-3x^2+x^3)(1-3x+x^2)(-1+2x)),{x,0,30}],x] (* or *) LinearRecurrence[{14,-81,254,-481,588,-485,270,-98,21,-2},{1,5,25,115,500,2092,8512,33910,132892,514079},30] (* Harvey P. Dale, Oct 03 2015 *)
Showing 1-2 of 2 results.