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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).

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%I A195399 #12 Nov 26 2024 16:30:03
%S A195399 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,
%T A195399 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,
%U A195399 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
%N 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).
%C A195399 See A195284 for definitions and a general discussion.
%H A195399 <a href="/index/Al#algebraic_04">Index entries for algebraic numbers, degree 4</a>
%e A195399 (A)=1.75938215709649255886516352490038207092333...
%t A195399 a = Sqrt[7]; b = 3; c = 4;
%t A195399 f = 2 a*b/(a + b + c);
%t A195399 x1 = Simplify[f*Sqrt[a^2 + (b + c)^2]/(b + c) ]
%t A195399 x2 = Simplify[f*Sqrt[b^2 + (c + a)^2]/(c + a) ]
%t A195399 x3 = f*Sqrt[2]
%t A195399 N[x1, 100]
%t A195399 RealDigits[%]    (* (A) A195399 *)
%t A195399 N[x2, 100]
%t A195399 RealDigits[%]    (* (B) A195400 *)
%t A195399 N[x3, 100]
%t A195399 RealDigits[%]    (* (C) A195401 *)
%t A195399 N[(x1 + x2 + x3)/(a + b + c), 100]
%t A195399 RealDigits[%]    (*  Philo(ABC,I) A195402 *)
%o A195399 (PARI) sqrt(8)*(7-sqrt(7))/7 \\ _Charles R Greathouse IV_, Nov 26 2024
%o A195399 (PARI) polrootsreal(49*x^4-896*x^2+2304)[3] \\ _Charles R Greathouse IV_, Nov 26 2024
%Y A195399 Cf. A195284, A195400, A195401, A195402.
%K A195399 nonn,cons
%O A195399 1,2
%A A195399 _Clark Kimberling_, Sep 17 2011