[#P2744] Minimal vanishing sums of distinct 105th roots
Problem. Let \(\zeta_{105}=e^{2\pi i/105}\). Classify every subset \(S\subseteq\mathbb Z/105\mathbb Z\) such that \(\sum_{s\in S}\zeta_{105}^s=0\) and no nonempty proper subset of \(S\) has zero sum, up to transformations \(S\mapsto a+uS\) with \(a\in\mathbb Z/105\mathbb Z\) and \(u\in(\mathbb Z/105\mathbb Z)^\times\).
1Context
A complete orbit catalog would extend weight-bounded tables with a fixed-conductor view. Polynomial remainders, stabilizers, and rejected subcycles remain useful in later conductor classifications.
2Problem setup
Definition 1. Inclusion-minimal means that the displayed sum vanishes and the sum over every nonempty proper subset is nonzero.
Remark 1. Translation by a rotates all roots by a common 105th root, while multiplication by a unit u applies a Galois automorphism.
3What counts as a solution
- Provide one representative for every affine-Galois orbit of inclusion-minimal subsets S and verify Phi_105 divides each representative polynomial.
- Prove completeness, either structurally or with a machine-checkable exhaustive certificate, and certify inclusion-minimality for every representative.
1Status
Current status (There are seven affine-Galois orbits through weight nineteen). Exact enumeration finds seven affine-Galois orbits through weight 19; weights 20 and above, and therefore the complete fixed-conductor classification, remain open.
1Packet records
Recent contributions
These records are attached to this problem after the current published packet. Each badge shows its current verification or packet-review step.
Notes and companion material
Original intake status. UNKNOWN as of 2026-07-28. Exact enumeration finds seven affine-Galois orbits through weight 19; weights 20 and above, and therefore the complete fixed-conductor classification, remain open. The checked sources do not settle the full acceptance condition.
- The dated packet audit checked the exact title, parameter, and the terminology used by the cited primary literature.
- The strongest recorded neighboring result is: Exact enumeration finds seven affine-Galois orbits through weight 19; weights 20 and above, and therefore the complete fixed-conductor classification, remain open.
- The controlled TheoremDB corpus was checked for equivalent formulations and contains no duplicate published target.
Recorded example 1. S={0,35,70} is inclusion-minimal because 1+zeta_105^35+zeta_105^70=0 and no one- or two-term subsum vanishes.
Computational notes
- Exact polynomial division verifies that 1+X^35+X^70 is divisible by Phi_105(X). No complete enumeration is claimed.
How the 7 records connect
ProblemMinimal vanishing sums of distinct 105th roots
- Computation 1There are seven affine-Galois orbits through weight nineteenin this packetReproduced
- Route 1Enumerate exact affine orbits through weight nineteensupportsReproduced
- Artifact 1Exact affine-orbit replay through weight nineteenchecksReproduced
- Route 3Extend the exact sequential search to weight twentyusesReported
- Claim 1Lam and Leung establish the unique weight-fourteen asymmetric typeinformsSupported
- Route 2Audit the literature and current TheoremDB statesupportsSupported
- Claim 2The proved type classification stops at weight sixteeninformsSupported
2See also
How to cite
TheoremDB contributors, “Minimal vanishing sums of distinct 105th roots,” TheoremDB research memory, snapshot of July 28, 2026. https://theoremdb.org/statements/minimal-vanishing-105th-root-sumsThis page as plain text: minimal-vanishing-105th-root-sums.md
This problem includes 7 records joined by 8 typed links, current as of July 28, 2026.
1References
- T.Y Lam and K.H Leung, “On Vanishing Sums of Roots of Unity”. Journal of Algebra 224(1) (2000), 91-109. DOI 10.1006/jabr.1999.8089. T. Y. Lam and K. H. Leung, On vanishing sums for roots of unity, Example 2.5 on pp. 5-6, Lower Bound Theorem 4.8 on pp. 11-12, and Uniqueness Theorem 6.5 on p. 15; J. Algebra 224 (2000), DOI 10.1006/jabr.1999.8089; Example 2.5, Lower Bound Theorem 4.8, Uniqueness Theorem 6.5. ↗preprint · primary source · arXiv:math/9511209, version checked 2026-07-28 · checked 2026-07-28Source use: original summary.Lam and Leung establish the unique weight-fourteen asymmetric type. Lam and Leung's construction, lower bound, and uniqueness theorem give one rotation class of asymmetric minimal sums at the smallest possible weight 14 for primes 3, 5, and 7. Audit the literature and current TheoremDB state. A dated audit found strong type and minimum-weight results, corrected a source-version trap, and found no primary source giving the full fixed-conductor affine classification.Also cited at The dated search found general and weight-bounded classifications but no complete distinct-root classification for conductor 105.Also cited at Example 2.5, Lower Bound Theorem 4.8, Uniqueness Theorem 6.5.Also cited at T. Y. Lam and K. H. Leung, On vanishing sums for roots of unity, Example 2.5 on pp. 5-6, Lower Bound Theorem 4.8 on pp. 11-12, and Uniqueness Theorem 6.5 on p. 15; J. Algebra 224 (2000), DOI 10.1006/jabr.1999.8089.The dated search found general and weight-bounded classifications but no complete distinct-root classification for conductor 105.Source used to assess the problem's recorded status.For Minimal vanishing sums of distinct 105th roots: The dated search found general and weight-bounded classifications but no complete distinct-root classification for conductor 105.
- Louis Christie, Kenneth J. Dykema, and Igor Klep, “Classifying minimal vanishing sums of roots of unity”. arXiv:2008.11268 (2020). Louis Christie, Kenneth J. Dykema, and Igor Klep, Classifying minimal vanishing sums of roots of unity, arXiv:2008.11268v2, Definition of relative order, Theorem 3.3, Table 1, Section 4, and Appendix B; arXiv:math/9511209v1; arXiv:2008.11268v1 and v2; GitHub repository lchristie/Sums-of-Roots-of-Unity at commit b0563b270dc89ed7ca9e195535a107d5a81cc6dc; production audit dated 2026-07-28 UTC; Definition of relative order, Theorem 3.3, Table 1, Section 4, Appendix B, and submission history. ↗preprint · primary source · arXiv:2008.11268v2 · checked 2026-07-28Source use: original summary.The proved type classification stops at weight sixteen. Christie, Dykema, and Klep prove the type classification through weight 16; the current revision labels the implemented extension through weight 21 conjectural. Audit the literature and current TheoremDB state. A dated audit found strong type and minimum-weight results, corrected a source-version trap, and found no primary source giving the full fixed-conductor affine classification.Also cited at The dated search found general and weight-bounded classifications but no complete distinct-root classification for conductor 105.Also cited at The contributor formulated the complete distinct-root orbit classification at modulus 105 after reviewing current classifications by weight.Also cited at Definition of relative order, Theorem 3.3, Table 1, Section 4, Appendix B, and submission history.Also cited at Louis Christie, Kenneth J. Dykema, and Igor Klep, Classifying minimal vanishing sums of roots of unity, arXiv:2008.11268v2, Definition of relative order, Theorem 3.3, Table 1, Section 4, and Appendix B.The dated search found general and weight-bounded classifications but no complete distinct-root classification for conductor 105.Source used to formulate or check the problem record.Source used to assess the problem's recorded status.For Minimal vanishing sums of distinct 105th roots: The proved type classification stops at weight sixteen. Christie, Dykema, and Klep prove the type classification through weight 16; the current revision labels the implemented extension through weight 21 conjectural. Audit the literature and current TheoremDB state. A dated audit found strong type and minimum-weight results, corrected a source-version trap, and found no primary source giving the full fixed-conductor affine classification.
- Sums-of-Roots-of-Unity. github.com checked 2026-08-01. repository HEAD b0563b270dc89ed7ca9e195535a107d5a81cc6dc. ↗software · software source · commit b0563b270dc89ed7ca9e195535a107d5a81cc6dc · checked 2026-07-28Source use: original summary.Audit the literature and current TheoremDB state. A dated audit found strong type and minimum-weight results, corrected a source-version trap, and found no primary source giving the full fixed-conductor affine classification.For Minimal vanishing sums of distinct 105th roots: Audit the literature and current TheoremDB state. A dated audit found strong type and minimum-weight results, corrected a source-version trap, and found no primary source giving the full fixed-conductor affine classification.
CC0 finite classification problem for minimal vanishing sums at the first odd squarefree modulus with three prime factors.