# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a201904 Showing 1-1 of 1 %I A201904 #5 Mar 30 2012 18:58:03 %S A201904 3,1,6,4,1,3,7,1,1,1,6,3,7,9,3,8,3,2,5,2,8,4,4,6,6,9,6,6,7,3,8,9,2,1, %T A201904 5,9,6,5,6,1,5,5,3,9,9,2,8,5,9,5,4,4,6,8,2,9,4,2,9,6,9,5,3,8,4,1,0,1, %U A201904 9,5,2,1,7,6,4,7,0,9,8,9,5,4,3,6,1,5,6,7,8,3,8,2,0,9,3,2,1,8,6 %N A201904 Decimal expansion of the greatest x satisfying x^2+4x+1=e^x. %C A201904 See A201741 for a guide to related sequences. The Mathematica program includes a graph. %e A201904 least: -3.73890200966899672518020580953927823014766... %e A201904 greatest: 3.164137111637938325284466966738921596561... %t A201904 a = 1; b = 4; c = 1; %t A201904 f[x_] := a*x^2 + b*x + c; g[x_] := E^x %t A201904 Plot[{f[x], g[x]}, {x, -4, 3.3}, {AxesOrigin -> {0, 0}}] %t A201904 r = x /. FindRoot[f[x] == g[x], {x, -3.8, -3.7}, WorkingPrecision -> 110] %t A201904 RealDigits[r] (* A201903 *) %t A201904 r = x /. FindRoot[f[x] == g[x], {x, 3.1, 3.2}, WorkingPrecision -> 110] %t A201904 RealDigits[r] (* A201904 *) %Y A201904 Cf. A201741. %K A201904 nonn,cons %O A201904 1,1 %A A201904 _Clark Kimberling_, Dec 06 2011 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE