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A202346
Decimal expansion of x > 0 satisfying 2*x + 2 = exp(x).
3
1, 6, 7, 8, 3, 4, 6, 9, 9, 0, 0, 1, 6, 6, 6, 0, 6, 5, 3, 4, 1, 2, 8, 8, 4, 5, 1, 2, 0, 9, 4, 5, 2, 3, 0, 8, 4, 8, 2, 4, 4, 5, 8, 7, 6, 5, 3, 5, 1, 6, 0, 2, 2, 1, 6, 3, 9, 8, 3, 4, 1, 8, 6, 8, 3, 9, 9, 0, 4, 7, 6, 4, 5, 6, 8, 5, 7, 1, 3, 4, 3, 6, 9, 9, 7, 4, 6, 9, 8, 2, 4, 1, 8, 8, 1, 2, 0, 6, 3
OFFSET
1,2
COMMENTS
See A202320 for a guide to related sequences. The Mathematica program includes a graph.
LINKS
EXAMPLE
x<0: -0.76803904701346556525568352607754...
x>0: 1.6783469900166606534128845120945230...
MATHEMATICA
u = 2; v = 2;
f[x_] := u*x + v; g[x_] := E^x
Plot[{f[x], g[x]}, {x, -3, 2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -.8, -.7}, WorkingPrecision -> 110]
RealDigits[r] (* A202345 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.6, 1.7}, WorkingPrecision -> 110]
RealDigits[r] (* A202346 *)
RealDigits[-1 - LambertW[-1, -Exp[-1]/2], 10, 100][[1]] (* G. C. Greubel, Nov 09 2017 *)
PROG
(PARI) solve(x=0, 2, 2*x+2-exp(x)) \\ Michel Marcus, Nov 09 2017
CROSSREFS
Cf. A202320.
Sequence in context: A010500 A175639 A256922 * A117022 A051994 A085661
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 17 2011
STATUS
approved