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Canonical Key
alternating_signs

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
r* ≈ 0.950
Radius of starlikeness r* ≈ 0.9500
disproven f is starlike on |z| < r*; the colored disk shows the certified region.

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Related

Facts (4)

Property Kind Params Holds Value / r Status Confidence
K membership {} -3.8277 unscreened -
r* radius {} - r ≤ 0.920 unscreened -
S* membership {} r ≤ 0.950 ✗ disproven proven
S membership {} - unscreened -

Verification Runs (3)

Verifier Property Direction Outcome Domain r Witness Engine
boundary_scan_centered_v31 starlike disproves pass 0.950 0.99*exp(i*3.400835) boundary_v3.1
pointwise_starlike_iv starlike disproves pass 0.990 [-0.9605927690132365, 0.23950267664367106] gft-0.1.0-reaudit-20260610
boundary_scan_polynomial starlike disproves pass 0.950 0.99*exp(i*3.40352) boundary_v3.0

Instances (1)

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