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A201927
Decimal expansion of the least x satisfying x^2+4x+4=e^x.
4
2, 3, 1, 4, 3, 6, 9, 9, 0, 2, 9, 6, 7, 6, 2, 8, 0, 1, 9, 1, 7, 3, 9, 1, 3, 3, 9, 2, 0, 4, 2, 9, 4, 7, 1, 8, 9, 3, 2, 0, 3, 5, 0, 5, 5, 7, 6, 8, 2, 8, 5, 8, 5, 9, 0, 7, 9, 3, 7, 5, 4, 4, 3, 2, 0, 9, 4, 9, 2, 5, 2, 5, 8, 4, 2, 1, 4, 5, 1, 0, 4, 0, 7, 3, 1, 4, 6, 5, 7, 5, 5, 4, 7, 5, 4, 9, 6, 6, 2
OFFSET
1,1
COMMENTS
See A201741 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: -2.3143699029676280191739133920...
nearest to 0: -1.53607809402693113051136705...
greatest: 3.3566939800333213068257690241...
MATHEMATICA
a = 1; b = 4; c = 4;
f[x_] := a*x^2 + b*x + c; g[x_] := E^x
Plot[{f[x], g[x]}, {x, -3, 3.5}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -2.4, -2.3}, WorkingPrecision -> 110]
RealDigits[r] (* A201927 *)
r = x /. FindRoot[f[x] == g[x], {x, -1.6, -1.5}, WorkingPrecision -> 110]
RealDigits[r] (* A201928 *)
r = x /. FindRoot[f[x] == g[x], {x, 3.3, 3.4}, WorkingPrecision -> 110]
RealDigits[r] (* A201929 *)
CROSSREFS
Cf. A201741.
Sequence in context: A140757 A258254 A100035 * A238442 A090244 A210976
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Dec 06 2011
STATUS
approved