A193078 Decimal expansion of the coefficient of x in the reduction of phi^(-x) by x^2->x+1, where phi=(1+sqrt(5))/2 is the golden ratio (A001622) (negated).
3, 9, 6, 8, 2, 1, 7, 6, 2, 2, 5, 4, 6, 3, 9, 9, 6, 6, 8, 6, 8, 3, 1, 5, 6, 0, 2, 9, 7, 3, 5, 3, 0, 1, 9, 7, 1, 6, 7, 6, 0, 2, 7, 5, 4, 8, 5, 1, 5, 4, 4, 8, 5, 3, 3, 0, 5, 9, 9, 0, 1, 0, 9, 9, 9, 9, 6, 1, 9, 7, 5, 4, 0, 3, 0, 0, 6, 9, 5, 4, 9, 7, 6, 3, 0, 7, 2, 8, 7, 1, 9, 2, 0, 9, 6, 8, 0, 7, 7, 7
Offset: 0
Examples
-0.39682176225463996686831560297353019716760...
Programs
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Mathematica
t = GoldenRatio f[x_] := t^(-x); r[n_] := Fibonacci[n]; c[n_] := SeriesCoefficient[Series[f[x], {x, 0, n}], n] u1 = N[Sum[c[n]*r[n], {n, 0, 100}], 100] RealDigits[u1, 10]
Formula
From Amiram Eldar, Jan 19 2022: (Start)
Equals Sum_{k>=0} (-log(phi))^k*Fibonacci(k)/k!.
Equals -(phi^sqrt(5) - 1)/(sqrt(5)*phi^phi). (End)
Comments