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Canonical Key
-log(1-z)
Closed Form
f(z) = -log(1-z)
Coefficient Formula
a_n = 1/n

Image domain \(f(\mathbb{D})\)

The image of the unit disk under \(f\): concentric circles \(|z|=r\) and radial spokes mapped through \(f(z)=z+a_2z^2+\dots\); the bold curve is the boundary \(f(e^{i\theta})\). Rendered in your browser from the certified Taylor coefficients - nothing is computed server-side.

Taylor series

Unit disk explorer - hover to evaluate

Hover over the disk

Related

Univalence Criteria

Schwarzian ladder estimate ||S(f)||
1.980
Screen only; univalence is inconclusive
Pre-Schwarzian ladder estimate ||T(f)||
1.990
Screen only; univalence is inconclusive

Facts (8)

Property Kind Params Holds Value / r Status Confidence
B membership {} - 1.9900 retracted -
K membership {} ✗ -11.4339 unscreened -
N membership {} - 1.9801 retracted -
||T(f)|| bound {} - 1.9900 retracted -
r* radius {} - r ≤ 0.960 🔬 screened numerical_strong
||S(f)|| bound {} - 1.9801 retracted -
S* membership {} - 0.5334 retracted -
S membership {} ✗ - unscreened -

Verification Runs (4)

Verifier Property Direction Outcome Domain r Witness Engine
boundary_scan_closed_form_v31 starlike proves pass 0.999 - boundary_v3.1
pointwise_becker_univalent_iv becker_univalent disproves pass 0.990 [-0.49500000000000044, -0.857365149746594] gft-0.1.0-reaudit-20260610
boundary_scan_centered_v31 starlike disproves pass 0.950 0.99*exp(i*6.023943) boundary_v3.1
boundary_scan_closed_form starlike proves pass 0.999 - boundary_v3.0

Instances (1)

{}
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