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.

A192950 a(n) = A192942(n)/2.

Original entry on oeis.org

0, 1, 5, 31, 224, 1844, 17028, 174284, 1958176, 23959760, 317128240, 4514617360, 68784608640, 1116787186240, 19248968150720, 351024831699520, 6752328440253440, 136640443206206720, 2901703626188801280, 64522443639953657600
Offset: 0

Views

Author

Clark Kimberling, Jul 13 2011

Keywords

Comments

See A192942.

Examples

			(See A192942.)
		

Crossrefs

Cf. A192942.

Programs

  • Magma
    SetDefaultRealField(RealField(100)); R:= RealField(); s:=Sqrt(5); [Round(s*Gamma(n+2+s)/Gamma(s+2) - Sin(Pi(R)*(s+3))*Gamma(s+1) *Gamma(n+2-s)/(Pi(R)*(s-1)))/10: n in [0..20]]; // G. C. Greubel, Jul 25 2019
    
  • Mathematica
    (* First program *)
    q = x^2; s = x + 1; z = 26;
    p[0, x]:= 1;
    p[n_, x_]:= (2*x + n)*p[n-1, x];
    Table[Expand[p[n, x]], {n, 0, 7}]
    reduce[{p1_, q_, s_, x_}]:= FixedPoint[(s PolynomialQuotient @@ #1 + PolynomialRemainder @@ #1 &)[{#1, q, x}] &, p1]
    t = Table[reduce[{p[n, x], q, s, x}], {n, 0, z}];
    u1 = Table[Coefficient[Part[t, n], x, 0], {n, 1, z}] (* A192941 *)
    u2 = Table[Coefficient[Part[t, n], x, 1], {n, 1, z}] (* A192942 *)
    u2/2 (* A192950 *)
    (* Additional programs *)
    With[{s = Sqrt[5]}, Table[FullSimplify[(s*Gamma[n+2+s]/Gamma[s+2] - Sin[Pi*(s+3)]*Gamma[s+1]*Gamma[n+2-s]/(Pi*(s-1)))/10], {n, 0, 20}]] (* G. C. Greubel, Jul 25 2019 *)
  • PARI
    default(realprecision, 100); vector(20, n, n--; s=sqrt(5); round(s*gamma(n+2+s)/gamma(s+2) - sin(Pi*(s+3))*gamma(s+1)*gamma(n+2-s)/(Pi*(s-1)))/10 ) \\ G. C. Greubel, Jul 25 2019
    
  • Sage
    s=sqrt(5); [round(s*gamma(n+2+s)/gamma(s+2) - sin(pi*(s+3))* gamma(s+1)*gamma(n+2-s)/(pi*(s-1)))/10 for n in (0..20)] # G. C. Greubel, Jul 25 2019

Formula

a(n) = 1/10*sqrt(5)*Gamma(n+2+sqrt(5))/Gamma(sqrt(5)+2) - 1/10*sin(Pi*(sqrt(5)+3))*Gamma(sqrt(5)+1)*Gamma(n+2-sqrt(5))/(Pi*(sqrt(5)-1)). - Vaclav Kotesovec, Oct 26 2012