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Beurling–Ahlfors transform constant

54a
Upper bound, last-listed row
| $1.575$ | [BJ2008] | Bañuelos–Janakiraman proved $\lVert B\rVert_p \le 1.575(p^*-1)$ for all $1<p<\infty$. [BJ2008-abs-ub1575] |
exact pinned row| $1.575$ | <a href="#BJ2008">[BJ2008]</a> | Bañuelos–Janakiraman proved $\lVert B\rVert_p \le 1.575(p^*-1)$ for all $1<p<\infty$. <a href="#BJ2008-abs-ub1575">[BJ2008-abs-ub1575]</a> |
tracked since 2026-07-24 — no movement seen yet
Lower bound, last-listed row
| $1$ | [Leh1965] | Lehto proved $\lVert B\rVert_p \ge p^*-1$, which implies $C_{54}\ge 1$. [BJ2008-Lehto-lb] |
exact pinned row| $1$ | <a href="#Leh1965">[Leh1965]</a> | Lehto proved $\lVert B\rVert_p \ge p^*-1$, which implies $C_{54}\ge 1$. <a href="#BJ2008-Lehto-lb">[BJ2008-Lehto-lb]</a> |
tracked since 2026-07-24 — no movement seen yet
Checked against material for its cited source
1 bound row(s) here have been checked against material for their cited source (1 drawn by position, 0 chosen because something already looked wrong). Across this whole ledger 70 row(s) have been drawn by position, against 691 rows that name a source, counted on 2026-09-27: 64 were checked against material for their cited sources and for 6 the cited source could not be read at all. 5 more were chosen for suspicion and checked; they are counted apart, because a set selected for suspicion carries no rate. A row not listed here has NOT been checked.
the mirrored file · upstream source · looks wrong?
Cite this rowBounds Ledger — Beurling–Ahlfors transform constant (54a) upper bound: $1.575$ (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/54a.html