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Decimal expansion of the number x satisfying x+3=exp(-x).
2

%I #15 Jun 11 2017 04:06:44

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

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

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

%N Decimal expansion of the number x satisfying x+3=exp(-x).

%C See A202322 for a guide to related sequences. The Mathematica program includes a graph.

%H G. C. Greubel, <a href="/A202323/b202323.txt">Table of n, a(n) for n = 0..5000</a>

%e x=-0.7920599684306770014183958778854220...

%t u = 3; v = 0;

%t f[x_] := u*x + v; g[x_] := E^x

%t Plot[{f[x], g[x]}, {x, -1, 2}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, 0.6, 0.7}, WorkingPrecision -> 110]

%t RealDigits[r] (* A202351 *)

%t r = x /. FindRoot[f[x] == g[x], {x, 1.5, 1.6}, WorkingPrecision -> 110]

%t RealDigits[r] (* A202352 *)

%t (* other program *)

%t RealDigits[ ProductLog[E^3] - 3, 10, 99] // First (* _Jean-François Alcover_, Feb 14 2013 *)

%o (PARI) lambertw(exp(3)) - 3 \\ _G. C. Greubel_, Jun 10 2017

%Y Cf. A202322.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Dec 18 2011

%E a(97)-a(98) corrected by _Jean-François Alcover_, Feb 14 2013