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A201895 Decimal expansion of the least x satisfying x^2+3x+1=e^x. 3

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

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

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

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

%N Decimal expansion of the least x satisfying x^2+3x+1=e^x.

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

%e least: -2.649219887767292965348496137953408152796...

%e greatest: 2.8931164309252712203155349313495308853...

%t a = 1; b = 3; c = 1;

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

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

%t r = x /. FindRoot[f[x] == g[x], {x, -2.7, -2.6}, WorkingPrecision -> 110]

%t RealDigits[r] (* A201895 *)

%t r = x /. FindRoot[f[x] == g[x], {x, 2.9, 3.0}, WorkingPrecision -> 110]

%t RealDigits[r] (* A201986 *) (* NOTE: 3 zeros *)

%Y Cf. A201741.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Dec 06 2011

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)