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A201903 Decimal expansion of the least x satisfying x^2+4x+1=e^x. 3

%I #5 Mar 30 2012 18:58:03

%S 3,7,3,8,9,0,2,0,0,9,6,6,8,9,9,6,7,2,5,1,8,0,2,0,5,8,0,9,5,3,9,2,7,8,

%T 2,3,0,1,4,7,6,6,8,8,9,7,0,7,8,6,0,7,2,8,2,2,0,0,9,9,5,7,9,2,4,2,6,0,

%U 6,8,0,9,5,0,9,5,6,0,2,8,1,5,4,6,6,1,1,4,3,9,1,8,8,9,8,5,0,7,5

%N Decimal expansion of the least x satisfying x^2+4x+1=e^x.

%C See A201741 for a guide to related sequences. The Mathematica program includes a graph.

%e least: -3.73890200966899672518020580953927823014766...

%e greatest: 3.164137111637938325284466966738921596561...

%t a = 1; b = 4; c = 1;

%t f[x_] := a*x^2 + b*x + c; g[x_] := E^x

%t Plot[{f[x], g[x]}, {x, -4, 3.3}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, -3.8, -3.7}, WorkingPrecision -> 110]

%t RealDigits[r] (* A201903 *)

%t r = x /. FindRoot[f[x] == g[x], {x, 3.1, 3.2}, WorkingPrecision -> 110]

%t RealDigits[r] (* A201904 *)

%Y Cf. A201741.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Dec 06 2011

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Last modified April 23 13:11 EDT 2024. Contains 371913 sequences. (Running on oeis4.)