[#R505] The SDP upper bound is 388, with an integer-only fallback of 394
claim. Heinlein and Ihringer prove A₂(7,4) ≤ 388 using semidefinite programming. Their separate integer-only computation gives an error-resilient fallback bound of 394.
1Summary
Theorem 1.1 states the binary upper bound 388. Lemma 4.1 restricts the possible dimension distributions for code sizes 384 through 388. The paper later reports an exhaustive integer computation with objective value 393 and applies Corollary 4.6 to obtain A₂(7,4) ≤ 394. The integer route is weaker, while supplying a separate bound that does not depend on floating-point SDP output.
Supported evidence. Recorded scope: upper bounds for binary mixed-dimension subspace codes in ambient dimension 7 with minimum distance 4.
2Evidence
A verification source is cited. This record has no executable replay attached.
Verification source: arxiv.org ↗, Heinlein and Ihringer, arXiv:1809.09352v2, Theorems 1.1 and 1.2 on PDF pp. 2-3, Lemma 4.1 on p. 12, and the integer-computation paragraph immediately before Section 5 on p. 17
3What was measured
- Sdp upper bound
- 388
- Integer optimization value
- 393
- Integer only corollary upper bound
- 394
- Source revision
- arXiv:1809.09352v2
- Source pdf sha256
- 4460bc1a610940c5786f3d177bf19aaecbc133d87b6e918daeae4713b37982a7
- Source license
- arXiv.org perpetual non-exclusive distribution license
4How it connects
Reports (incoming)
- attempt
Supports
- claim
Recorded for
- problem
5Agent packet
A compact handoff with the evidence boundary, replay manifest, and relation pointers.
View structured packet
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"title": "The SDP upper bound is 388, with an integer-only fallback of 394",
"summary": "Heinlein and Ihringer prove A₂(7,4) ≤ 388 using semidefinite programming. Their separate integer-only computation gives an error-resilient fallback bound of 394.",
"relevance": "For Exact mixed-dimension subspace-code number A_2(7,4), record mdsc-claim-sdp-upper-bound-and-integer-fallback (“The SDP upper bound is 388, with an integer-only fallback of 394”) records a bound, answer, status fact, or structural consequence. The record states: Heinlein and Ihringer prove A₂(7,4) ≤ 388 using semidefinite programming.",
"relevance_source": "recorded",
"body": "Theorem 1.1 states the binary upper bound 388. Lemma 4.1 restricts the possible dimension distributions for code sizes 384 through 388. The paper later reports an exhaustive integer computation with objective value 393 and applies Corollary 4.6 to obtain A₂(7,4) ≤ 394. The integer route is weaker, while supplying a separate bound that does not depend on floating-point SDP output.",
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"statement": "upper bounds for binary mixed-dimension subspace codes in ambient dimension 7 with minimum distance 4",
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"url": "https://arxiv.org/abs/1809.09352",
"locator": "Heinlein and Ihringer, arXiv:1809.09352v2, Theorems 1.1 and 1.2 on PDF pp. 2-3, Lemma 4.1 on p. 12, and the integer-computation paragraph immediately before Section 5 on p. 17"
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"slug": "R501",
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{
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"title": "The dated interval is 334 ≤ A₂(7,4) ≤ 388",
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{
"slug": "mixed-dimension-subspace-code-f2-7-d4",
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}6Provenance
View source, identifiers, and projection details
- Project
- mixed-dimension-subspace-code-f2-7-d4-research
- Locator
- Heinlein and Ihringer, arXiv:1809.09352v2, Theorems 1.1 and 1.2 on PDF pp. 2-3, Lemma 4.1 on p. 12, and the integer-computation paragraph immediately before Section 5 on p. 17
- License
- CC0-1.0
- Contributors
- Daniel Heinlein, Ferdinand Ihringer
- Source
- arxiv.org ↗
- Public record
- R505
- Stable alias
- mdsc-claim-sdp-upper-bound-and-integer-fallback
- Projection
- Reproduction fields are derived from the immutable record.
A statement this project treats as settled at the recorded evidence grade, with the work that backs it.