| $2$ | | Trivial geometric bound since all zeroes of $f$ and $f'$ lie in the closed unit disk. |tracked since 2026-07-24 — no movement seen yet
Lower bound, last-listed row
| $1$ | [[Tao2022](#Tao2022)] | Example $f(z)=z^n-1$, $\lambda_0=1$: the critical points are at $0$ and lie on $\partial D(\lambda_0,1)$. [Tao2022-example-zn1] |exact pinned row| $1$ | [[Tao2022](#Tao2022)] | Example $f(z)=z^n-1$, $\lambda_0=1$: the critical points are at $0$ and lie on $\partial D(\lambda_0,1)$. <a href="#Tao2022-example-zn1">[Tao2022-example-zn1]</a> |tracked since 2026-07-24 — no movement seen yet
Cite this rowBounds Ledger — Sendov radius constant (69a)
upper bound: $2$ (tracked since 2026-07-24 — no movement seen yet)
lower bound: $1$ (tracked since 2026-07-24 — no movement seen yet)
Mirrored from teorth/optimizationproblems@2c1968c. These are the last-listed rows of that constant's bounds table — a listing position, not a statement that this bound is the strongest or most recent. A snapshot at that sha, not a live read.
https://u00dxk2.github.io/bounds-ledger/c/69a.html