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.
%I A197584 #17 Feb 16 2025 05:40:15 %S A197584 4,5,0,4,5,7,4,9,4,1,3,6,7,2,8,7,6,5,2,0,5,1,8,4,1,7,8,8,6,5,8,8,3,4, %T A197584 4,7,1,4,0,9,5,4,3,3,5,9,2,1,7,0,2,3,3,7,6,9,1,5,4,9,8,3,2,7,8,1,0,0, %U A197584 9,0,1,3,3,8,6,6,3,5,0,2,5,2,8,5,5,1,7,5,5,1 %N A197584 Decimal expansion of least x>0 having cos(Pi*x/3)=(cos(x/3))^2. %C A197584 This number is irrational. I cannot prove it to be algebraic or transcendental. - _Charles R Greathouse IV_, Feb 16 2025 %F A197584 Equals 3*A197515. - _R. J. Mathar_, Oct 18 2011 %e A197584 4.504574941367287652051841788658834471409543359217023376915498327810090... %p A197584 fsolve(cos(Pi*x/3)-cos(x/3)^2,x=1..5) ; # _R. J. Mathar_, Oct 18 2011 %o A197584 (PARI) solve(x=4,5,cos(Pi/3*x)-cos(x/3)^2) \\ _Charles R Greathouse IV_, Oct 18 2011 %Y A197584 Cf. A197133. %K A197584 nonn,cons %O A197584 1,1 %A A197584 _Clark Kimberling_, Oct 16 2011 %E A197584 Corrected by _Charles R Greathouse IV_, Oct 18 2011