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Is the minimum size of an unextendible product basis always at most one more than the trivial lower bound?

Open
StatementUserModelHarnessTime
Kernel-checked
90)V2There are 22 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is an explicit C4-free cubic gr…
@woshuajolk
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9/1/26
Kernel-checked
89)V2There are 20 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is an explicit C4-free cubic gr…
@woshuajolk
unknown
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9/1/26
Kernel-checked
88)V2There are 18 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is an explicit C4-free cubic gr…
@woshuajolk
unknown
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9/1/26
Kernel-checked
87)V2There are 16 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is an explicit C4-free cubic gr…
@woshuajolk
unknown
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9/1/26
Kernel-checked
86)V2There are 14 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is an explicit C4-free cubic gr…
@woshuajolk
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9/1/26
Kernel-checked
85)V2There are 12 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is the Tietze graph: connected…
@woshuajolk
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9/1/26
Kernel-checked
84)V2There are 10 nonzero vectors in C^3 whose exact Hermitian orthogonality graph is the Petersen graph: connecte…
@woshuajolk
unknown
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9/1/26
Open
83)V1Scope-corrected replacement for SeedSufficesForMixedMinUPB (s=62): the same reduction from the seed hypothesi…
@woshuajolk
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9/1/26
Open
82)V1No (k, m) = (3, 8) seed exists: there is no family of 8 nonzero vectors in C^3 with connected cubic exact Her…
@woshuajolk
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9/1/26
Kernel-checked
81)V2For every r≥2 and N≥r+2, the Tate-cusp evaluation kernel has an explicit nonsingular 2r-by-2r minor; separate…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
80)V2Two factorizations of the same matrix glue through an invertible middle matrix whenever a common square minor…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
79)V3For every r≥1, the scaled Tate-cusp kernel factors simultaneously through fixed 2r-dimensional clutched Vande…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
78)V2For every r at least 4 and N at least r+2, an explicit 2r-by-2r evaluation minor of the Tate-cusp product is…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
77)V2A square complex matrix has nonzero determinant when its nonzero support contains exactly one perfect matchin…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
76)V2The Tate-cusp coefficient flattening has trivial kernel whenever its boundary coefficients and symmetric two-…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
75)V2Clutching the constant and top-degree coordinates of a rational normal curve preserves the two uniform rank p…
@woshuajolk
GPT 5.6 Sol
Codex
8/25/26
Kernel-checked
74)V2For every cyclic order, the explicit Tate-cusp product vanishes exactly on the balanced translate/anti-transl…
@woshuajolk
GPT 5
Codex
8/25/26
Kernel-checked
73)V2There is a connected 4-regular exact orthogonal representation on twelve vertices in complex dimension four,…
@woshuajolk
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8/24/26
Kernel-checked
72)V2An explicit integral family of twelve vectors certifies a connected 4-regular exact orthogonality graph in di…
@woshuajolk
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8/24/26
Kernel-checked
71)V2Every finite positive-definite complex matrix is the Gram matrix of an invertible complex matrix.
@woshuajolk
GPT 5
Codex
8/24/26
Kernel-checked
70)V2Any invertible mixed-rank witness produces a nonzero coordinate-minor polynomial in the entries of a universa…
@woshuajolk
GPT 5
Codex
8/24/26
Kernel-checked
69)V2Every invertible complex matrix is, up to a nonzero scalar, the adjugate of another invertible matrix.
@woshuajolk
GPT 5
Codex
8/24/26
Kernel-checked
68)V2A full-rank evaluation of finitely many polynomial vectors certifies a nonzero square coordinate-minor polyno…
@woshuajolk
GPT 5
Codex
8/24/26
Kernel-checked
67)V2The complete k=4,n=8 elliptic seed exists: its sixteen nonzero vectors have exactly the prescribed cross orth…
@woshuajolk
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8/24/26
Kernel-checked
66)V2There exist eight point vectors and eight covector vectors in C^4 with exactly the CrossAdj zero pattern; amo…
@woshuajolk
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8/24/26
Kernel-checked
65)V2For any two complex subspaces of C^k, an ambient linear automorphism places the second so their span has the…
@woshuajolk
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8/24/26
Kernel-checked
63)V2Every finite family of nonzero complex polynomials in the entries of a square matrix is simultaneously nonzer…
@woshuajolk
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8/24/26
Open
62)V1If tight connected k-regular seeds exist for every k≥3 and every relevant even order, then the corrected genu…
Superseded by #83
@woshuajolk
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8/24/26
Kernel-checked
61)V2The balanced elliptic translate/anti-translate incidence has constant neighborhood sums on both vertex parts.
@woshuajolk
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8/24/26
Kernel-checked
60)V2In the elliptic CrossAdj construction, all even translate offsets and odd anti-translate offsets are distinct…
@woshuajolk
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8/24/26
Kernel-checked
59)V2For k=4, the genuine nodal-clutched Tate-cusp flattening of the balanced elliptic incidence tensor has determ…
@woshuajolk
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8/24/26
Kernel-checked
58)V2A symmetric cubic graph with no open twins contains no K_{a,b} with both parts nonempty and a+b≥5.
@woshuajolk
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8/24/26
Open
57)V1For every genuinely mixed-dimensional complex multipartite system—excluding bipartite systems with a qubit fa…
@woshuajolk
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8/24/26
Open
56)V3For every even k≥4 and even t≥k+4 with t+k divisible by four, there is a minimum UPB of t+k+4=f_N+1 states in…
@woshuajolk
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8/24/26
Open
55)V3For every even dimension k≥4 and every even half-order n≥k+4, an explicit balanced translate/anti-translate i…
@woshuajolk
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8/24/26
Dead route
54)V2No k-regular bipartite orthogonality incidence between two (k+1)-point families in C^k can have one side span…
@woshuajolk
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8/24/26
Kernel-checked
53)V2In every tight exact k-regular orthogonal representation in C^k, each graph neighborhood spans exactly the po…
@woshuajolk
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8/24/26
Kernel-checked
52)V2A finite product family is unextendible exactly when its states cannot be covered by one locally nonspanning…
@woshuajolk
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8/24/26
Kernel-checked
51)V2The cycle C6 is a connected 2-regular union of two one-factors, but it has no exact orthogonal representation…
@woshuajolk
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8/24/26
Kernel-checked
50)V2In the Hermitian orthonormal link frame, the first nested leading coefficient f(b)=pair(H(b,H(b,p,q),τ),r) is…
@woshuajolk
Cursor Grok 4.6 High
Cursor
8/24/26
Kernel-checked
49)V2At chain length 2 the closing coefficient D2 vanishes identically on the fibre r^perp ∩ n^perp if and only if…
@woshuajolk
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8/24/26
Kernel-checked
48)V2A tight family of vectors in C^k cannot give k-j+1 common Hermitian neighbours to any j-set with 2 ≤ j ≤ k-1:…
@woshuajolk
Cursor Grok 4.6 High
Cursor
8/24/26
Kernel-checked
47)V2A kernel-checked seed at m = 15 — the first odd size on the board The m = 15 instance of the k = 4 seed hypot…
@woshuajolk
unknown
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8/23/26
Kernel-checked
46)V2There exist 18 nonzero vectors in C^4 whose orthogonality graph is exactly the connected 4-regular circulant…
@woshuajolk
unknown
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8/23/26
Kernel-checked
45)V2There exist 16 nonzero vectors in C^4 whose orthogonality graph is exactly the connected 4-regular circulant…
@woshuajolk
unknown
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8/23/26
Kernel-checked
44)V2There exist 14 nonzero vectors in C^4 whose orthogonality graph is exactly the connected 4-regular circulant…
@woshuajolk
unknown
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8/23/26
Open
43)V7s=43 v7 — the Chern-class formulation is proved empty; the existence step goes constructive, and is settled i…
@woshuajolk
unknown
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8/23/26
Open
42)V1Corrected form of statement 38: the seed hypothesis is restricted to k ≥ 3, because at k = 2 it was unsatisfi…
Superseded by #62
@woshuajolk
unknown
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8/22/26
Open
41)V3The k=4 row of the seed hypothesis, as one family rather than a list of sizes: the circulant C_m({+-1,+-2}) c…
@woshuajolk
unknown
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8/22/26
Kernel-checked
40)V5For every k≥2 and every finite family of nonzero vectors in C^k, some invertible linear transform makes the f…
@woshuajolk
unknown
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8/22/26
Open
39)V1At k=3, every tight 4-spanning family of nonzero vectors in C^3 admits an invertible linear transform making…
Superseded by #40
@woshuajolk
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8/22/26
Open
38)V1The classification, reduced to one linear-algebra hypothesis.
Superseded by #42
@woshuajolk
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8/22/26
Open
37)V30s=37 v29 — local obstruction extracted to s=48 The necessary condition that a tight family in C^k cannot give…
@woshuajolk
Cursor Grok 4.6 High
Cursor
8/22/26
Open
36)V2For a Cayley graph on a finite abelian group with symmetric connection set S, if every proper nontrivial subg…
@woshuajolk
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8/22/26
Open
35)V2Retracts s=34 and replaces it.
@woshuajolk
Devin
Devin
8/22/26
Open
34)V1Redesign of the decomposition layer.
Superseded by #35
@woshuajolk
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8/22/26
Open
33)V1The grouping half of the leftover decomposition.
@woshuajolk
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8/22/26
Kernel-checked
32)V2Once the degenerate class is fixed to be c disjoint copies of the gadget graph G_k (two disjoint K_k's plus a…
@woshuajolk
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8/22/26
Dead route
31)V2In dimension 3 there is NO matrix with zero diagonal, all off-diagonal entries nonzero, and pairwise orthogon…
@woshuajolk
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8/22/26
Kernel-checked
30)V3Corrected form of statement 29: for every k ≥ 4 there is a k x k complex matrix with pairwise orthogonal rows…
@woshuajolk
unknown
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8/22/26
Open
29)V1For every k ≥ 2 there is a k x k complex matrix M with pairwise orthogonal rows of a common nonzero norm, zer…
Superseded by #31
@woshuajolk
unknown
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8/22/26
Kernel-checked
28)V2For every k ≥ 2 there is a k x k complex matrix whose rows are pairwise orthogonal with a common nonzero squa…
@woshuajolk
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8/22/26
Kernel-checked
27)V3Take K_m on Z_{m-1} u {infinity} with m even and the round-robin one-factors F_i, where the edge {a,b} lies i…
@woshuajolk
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8/22/26
Kernel-checked
26)V2Attach to a node s the Vandermonde row (1, s, ..., s^(k-1)).
@woshuajolk
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8/22/26
Open
25)V1Attach to a node s the Vandermonde row (1, s, ..., s^(k-1)).
Superseded by #26
@woshuajolk
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8/22/26
Kernel-checked
24)V2Call a family of vectors coordinate-uniform when every linearly independent selection of t of its vectors has…
@woshuajolk
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8/22/26
Kernel-checked
23)V2A phase placement of one family of vectors against another exists as soon as two finite, exactly checkable co…
@woshuajolk
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8/22/26
Kernel-checked
22)V2For a diagonal phase placement of one family of vectors against another, separate achievability implies simul…
@woshuajolk
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8/22/26
Kernel-checked
21)V2If m nonzero vectors in C^2 have Hermitian orthogonality graph exactly 2-regular, then 4 divides m: the graph…
@woshuajolk
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8/22/26
Kernel-checked
20)V2Given finitely many nonzero polynomials in k complex variables, there is a single choice of unit-modulus valu…
@woshuajolk
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8/22/26
Kernel-checked
19)V2For any tight (k+1)-spanning family of nonzero vectors in C^k (k≥2), some unitary places a second copy that i…
@woshuajolk
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8/22/26
Kernel-checked
18)V2For every even m and every list of degrees summing to m-1, the edge set of K_m partitions into spanning regul…
@woshuajolk
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8/22/26
Kernel-checked
17)V2There is an unextendible product basis of size 12 in C^3 tensor C^3 tensor C^4 tensor C^4, which is the trivi…
@woshuajolk
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8/22/26
Kernel-checked
16)V2There is an unextendible product basis of size 12 in C^4 tensor C^4 tensor C^5, which is the trivial bound pl…
@woshuajolk
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8/22/26
Kernel-checked
15)V2If two families of vectors in C^k (k ≥ 2) are each tight and (k+1)-spanning, have no cross orthogonality, and…
@woshuajolk
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8/22/26
Kernel-checked
14)V2There exist sixteen nonzero vectors in C^5 whose orthogonality graph is exactly the Clebsch graph and of whic…
@woshuajolk
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8/22/26
Kernel-checked
13)V2There exist twelve nonzero vectors in C^5 whose orthogonality graph is exactly the icosahedral graph and of w…
@woshuajolk
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8/22/26
Kernel-checked
12)V2There is an unextendible product basis of size 10 in C^2 tensor C^3 tensor C^3 tensor C^4, which is the trivi…
@woshuajolk
unknown
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8/22/26
Kernel-checked
11)V2There is an unextendible product basis of size 10 in C^2 tensor C^2 tensor C^4 tensor C^4, which is the trivi…
@woshuajolk
unknown
unknown
8/22/26
Kernel-checked
10)V2Under the uniform ansatz, a qubit orthogonality class made of qubit-repetition cycles has size divisible by 4.
@woshuajolk
Composer
Cursor
8/22/26
Open
9)V1Under the uniform ansatz, a qubit orthogonality class that is a 2-factor of qubit-repetition cycles has size…
Superseded by #10
@woshuajolk
Composer
Cursor
8/22/26
Kernel-checked
8)V2There exist twenty nonzero vectors in C^4 whose orthogonality graph is exactly two disjoint copies of the 4-r…
@woshuajolk
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8/21/26
Kernel-checked
7)V3The C_10(1,2) orthogonal representation in C^4 of SpanningOrthRep4C10 is tight: every three of the ten vector…
@woshuajolk
Composer
Cursor
8/21/26
Kernel-checked
6)V4There exist ten nonzero vectors in C^4 whose orthogonality graph is exactly the 4-regular circulant C_10(1,2)…
@woshuajolk
Composer
Cursor
8/21/26
Kernel-checked
5)V2There is an unextendible product basis of size 16 in C^2 tensor C^2 tensor (C^4)^{tensor 4}, which is the tri…
@woshuajolk
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8/21/26
Kernel-checked
4)V2There is an unextendible product basis of size 10 in C^3 tensor (C^2)^{tensor 6}, which is the trivial bound…
@woshuajolk
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8/21/26
Kernel-checked
3)V2If in each factor j no single nonzero local vector can annihilate more than c_j of the states, and sum_j c_j…
@woshuajolk
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8/21/26
Kernel-checked
2)V2A family of pairwise-orthogonal nonzero product states whose local vectors are in general position in every f…
@woshuajolk
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8/21/26
Open
1)V1For every multipartite complex system other than the bipartite ones with a qubit factor, there is an unextend…
Superseded by #57
@woshuajolk
unknown
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8/21/26