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.

A195399 Decimal expansion of shortest length, (A), of segment from side AB through incenter to side AC in right triangle ABC with sidelengths (a,b,c)=(sqrt(7),3,4).

Original entry on oeis.org

1, 7, 5, 9, 3, 8, 2, 1, 5, 7, 0, 9, 6, 4, 9, 2, 5, 5, 8, 8, 6, 5, 1, 6, 3, 5, 2, 4, 9, 0, 0, 3, 8, 2, 0, 7, 0, 9, 2, 3, 3, 3, 8, 0, 9, 1, 3, 8, 8, 5, 4, 5, 5, 9, 0, 2, 6, 6, 5, 7, 5, 0, 5, 6, 7, 4, 7, 1, 6, 9, 1, 9, 7, 9, 7, 9, 3, 7, 4, 3, 5, 5, 4, 2, 1, 6, 8, 6, 5, 2, 7, 1, 7, 1, 1, 7, 4, 6, 9, 6
Offset: 1

Views

Author

Clark Kimberling, Sep 17 2011

Keywords

Comments

See A195284 for definitions and a general discussion.

Examples

			(A)=1.75938215709649255886516352490038207092333...
		

Crossrefs

Programs

  • Mathematica
    a = Sqrt[7]; b = 3; c = 4;
    f = 2 a*b/(a + b + c);
    x1 = Simplify[f*Sqrt[a^2 + (b + c)^2]/(b + c) ]
    x2 = Simplify[f*Sqrt[b^2 + (c + a)^2]/(c + a) ]
    x3 = f*Sqrt[2]
    N[x1, 100]
    RealDigits[%]    (* (A) A195399 *)
    N[x2, 100]
    RealDigits[%]    (* (B) A195400 *)
    N[x3, 100]
    RealDigits[%]    (* (C) A195401 *)
    N[(x1 + x2 + x3)/(a + b + c), 100]
    RealDigits[%]    (*  Philo(ABC,I) A195402 *)
  • PARI
    sqrt(8)*(7-sqrt(7))/7 \\ Charles R Greathouse IV, Nov 26 2024
    
  • PARI
    polrootsreal(49*x^4-896*x^2+2304)[3] \\ Charles R Greathouse IV, Nov 26 2024