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Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

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Claim. Let 3≤m≤323\le m\le32, put n=2mn=2m, and let rr be real with cos⁡(π/m)<r<sec⁡(π/m)\cos(\pi/m)<r<\sec(\pi/m). The nn points of the plane, written as complex numbers,

Ak=e2πik/m,Bk=re(2k+1)πi/m,0≤k<m,A_k=e^{2\pi ik/m},\qquad B_k=re^{(2k+1)\pi i/m},\qquad 0\le k<m,

form a strictly convex polygon, and some vertex has at least m=⌊n/2⌋m=\lfloor n/2\rfloor distinct distances to the other vertices. Let 8≤n≤248\le n\le24 and let s>0s>0 be real. The nn points

pk=(cos⁡(2πk/n),s sin⁡(2πk/n)),0≤k<n,p_k=\bigl(\cos(2\pi k/n),\sqrt s\,\sin(2\pi k/n)\bigr),\qquad 0\le k<n,

form a strictly convex polygon, and some vertex has at least ⌊n/2⌋\lfloor n/2\rfloor distinct distances to the other vertices. Thus neither family contains a counterexample in these ranges.

Covers. Two one-parameter families of convex polygons on Problem 982: the half-step concentric pairs of regular mm-gons, of even orders 6≤n≤646\le n\le64, and the regular nn-gons stretched along the fixed coordinate axes, of orders 8≤n≤248\le n\le24. It settles no order nn: other convex nn-gons, other angular offsets between the two orbits, further radial orbits, stretches along other axes and all orders outside these ranges are not covered, and the problem remains open.

Standing. Tier 0. The reduction to finitely many critical parameters, the strict-convexity tests and the census are author-recorded by Plasma AI, without independent review. The lead's evidence re-runs the exact enumeration in cyclotomic arithmetic, with certified real enclosures deciding only strict signs; it is author evidence and confers no tier. No Lean proof is asserted. Catalog acceptance is pending.

Depends on. the symmetric-family census lead (tier 0), with its critical-parameter reduction and its exact census.