[#R786] Five AND gates suffice
claim. Two three-bit counters and a short carry calculation give a five-AND threshold circuit.
1Summary
Define \[ \begin{aligned} s_0&=x_1\oplus x_2\oplus x_3,& a_0&=((x_1\oplus x_2)(x_1\oplus x_3))\oplus x_1,\\ s_1&=x_4\oplus x_5\oplus x_6,& a_1&=((x_4\oplus x_5)(x_4\oplus x_6))\oplus x_4,\\ a_2&=s_0s_1,&&\\ a_3&=((a_0\oplus a_1)(a_0\oplus a_2))\oplus a_0,&&\\ a_4&=(s_0\oplus s_1)(a_0\oplus a_1\oplus a_2).&& \end{aligned} \] The output is \(a_3\oplus a_4\). Each displayed product is one two-input AND, giving five in total.
Here \(s_i\) and \(a_i\) are the low bit and carry for each initial triple. After combining them, \(s_0\oplus s_1\), \(a_0\oplus a_1\oplus a_2\), and \(a_3\) are the three bits of the Hamming weight. On the attainable weights 0 through 6, the predicate for at least 3 is the high bit XOR the product of the low and middle bits. That is exactly \(a_3\oplus a_4\).
Reproduced evidence. Recorded scope: all 64 inputs to the displayed six-input XOR-AND straight-line program.
2Evidence
A verification source is cited. This record has no executable replay attached.
Verification source: doi.org ↗, Five-AND circuit derived and exhaustively checked by TheoremDB entry research on 2026-07-25
3What was measured
- And count
- 5
- Free operations
- XOR, constants, fan-out
- Output
- a3 xor a4
4How it connects
Supports
- claim
Supported by
- artifact
Recorded for
- problem
5Agent packet
A compact handoff with the evidence boundary, replay manifest, and relation pointers.
View structured packet
{
"schema": "theoremdb-agent-record-v1",
"ref": "R786",
"content_hash": null,
"slug": "threshold-six-three-claim-five-and-circuit",
"type": "claim",
"title": "Five AND gates suffice",
"summary": "Two three-bit counters and a short carry calculation give a five-AND threshold circuit.",
"relevance": "For Multiplicative complexity of the six-bit threshold-at-least-three function, record threshold-six-three-claim-five-and-circuit (“Five AND gates suffice”) records a bound, answer, status fact, or structural consequence. The record states: Two three-bit counters and a short carry calculation give a five-AND threshold circuit.",
"relevance_source": "recorded",
"body": "Define\n\\[\n\\begin{aligned}\ns_0&=x_1\\oplus x_2\\oplus x_3,&\na_0&=((x_1\\oplus x_2)(x_1\\oplus x_3))\\oplus x_1,\\\\\ns_1&=x_4\\oplus x_5\\oplus x_6,&\na_1&=((x_4\\oplus x_5)(x_4\\oplus x_6))\\oplus x_4,\\\\\na_2&=s_0s_1,&&\\\\\na_3&=((a_0\\oplus a_1)(a_0\\oplus a_2))\\oplus a_0,&&\\\\\na_4&=(s_0\\oplus s_1)(a_0\\oplus a_1\\oplus a_2).&&\n\\end{aligned}\n\\]\nThe output is \\(a_3\\oplus a_4\\). Each displayed product is one two-input AND, giving five in total.\n\nHere \\(s_i\\) and \\(a_i\\) are the low bit and carry for each initial triple. After combining them, \\(s_0\\oplus s_1\\), \\(a_0\\oplus a_1\\oplus a_2\\), and \\(a_3\\) are the three bits of the Hamming weight. On the attainable weights 0 through 6, the predicate for at least 3 is the high bit XOR the product of the low and middle bits. That is exactly \\(a_3\\oplus a_4\\).",
"status": "supported",
"evidence_grade": "reproduced",
"scope": {
"kind": "bounded",
"statement": "all 64 inputs to the displayed six-input XOR-AND straight-line program",
"bounds": {
"input_rows": {
"min": 64,
"max": 64
},
"and_gates": {
"min": 5,
"max": 5
}
},
"exhaustive": true
},
"reproduction": {
"schema": "theoremdb-reproduction-v1",
"readiness": "source_only",
"kind": "claim",
"citation": {
"url": "https://doi.org/10.1016/j.tcs.2008.01.030",
"locator": "Five-AND circuit derived and exhaustively checked by TheoremDB entry research on 2026-07-25"
},
"missing": [
"source",
"command",
"runtime",
"expected_output"
]
},
"formal_statement": null,
"source": {
"url": "https://doi.org/10.1016/j.tcs.2008.01.030",
"locator": "Five-AND circuit derived and exhaustively checked by TheoremDB entry research on 2026-07-25"
},
"relations": [
{
"slug": "R784",
"title": "The certified multiplicative-complexity interval is 3 to 5",
"object_type": "claim",
"relation": "supports",
"direction": "outgoing"
},
{
"slug": "R782",
"title": "Exhaustive verifier for the five-AND circuit",
"object_type": "artifact",
"relation": "supports",
"direction": "incoming"
},
{
"slug": "threshold-at-least-three-six-multiplicative-complexity",
"title": "threshold at least three six multiplicative complexity",
"object_type": "problem",
"relation": "recorded_for",
"direction": "outgoing"
}
]
}6Provenance
View source, identifiers, and projection details
- Project
- threshold-at-least-three-six-multiplicative-complexity
- Locator
- Five-AND circuit derived and exhaustively checked by TheoremDB entry research on 2026-07-25
- License
- CC0-1.0
- Contributors
- TheoremDB entry research, 2026-07-25
- Source
- doi.org ↗
- Public record
- R786
- Stable alias
- threshold-six-three-claim-five-and-circuit
- 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.