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.

A195341 Decimal expansion of shortest length, (B), of segment from side BC through incenter to side BA in right triangle ABC with sidelengths (a,b,c)=(1,2,sqrt(5)).

Original entry on oeis.org

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

Views

Author

Clark Kimberling, Sep 16 2011

Keywords

Comments

See A195284 for definitions and a general discussion.

Examples

			0.898055953159170744883890303595053575158424964642...
		

Crossrefs

Cf. A195284.

Programs

  • Mathematica
    a = 1; b = 2; c = Sqrt[5]; 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) A195340 *)
    N[x2, 100]
    RealDigits[%] (* (B) A195341 *)
    N[x3, 100]
    RealDigits[%] (* (C) A195342 *)
    N[(x1 + x2 + x3)/(a + b + c), 100]
    RealDigits[%] (* Philo(ABC,I) A195343 *)
  • PARI
    polrootsreal(x^4 - 100*x^2 + 80)[3] \\ Charles R Greathouse IV, Feb 11 2025

Extensions

a(99)-a(100) corrected by Georg Fischer, Jul 18 2021