Pith Number

pith:ICIMLZ2D

pith:2026:ICIMLZ2DTCQM6OZ7CY2VKJXB7K

not attested not anchored not stored refs pending

An approximation notion between P and FPTAS

Erel Segal-Halevi, Samuel Bismuth

A new approximation notion for NP-hard problems is strictly stronger than FPTAS but weaker than polynomial-time solvability.

arxiv:2603.17489 v4 · 2026-03-18 · cs.CC

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\usepackage{pith}
\pithnumber{ICIMLZ2DTCQM6OZ7CY2VKJXB7K}

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Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Claims

C1strongest claim

We prove that (assuming P != NP) the new notion is strictly stronger than FPTAS, but strictly weaker than having a polynomial-time algorithm.

C2weakest assumption

The optimization problems must be representable by binary functions, and the standard assumption P ≠ NP must hold for the strict separation to be meaningful.

C3one line summary

A new approximation notion for binary-function NP-hard problems is strictly stronger than FPTAS yet strictly weaker than polynomial-time algorithms, assuming P ≠ NP.

Receipt and verification

First computed	2026-07-13T01:18:05.533589Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

4090c5e74398a0cf3b3f16355526e1fab34f8392f551a8fb7792176c2177b884

Aliases

arxiv: 2603.17489 · arxiv_version: 2603.17489v4 · doi: 10.48550/arxiv.2603.17489 · pith_short_12: ICIMLZ2DTCQM · pith_short_16: ICIMLZ2DTCQM6OZ7 · pith_short_8: ICIMLZ2D

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/ICIMLZ2DTCQM6OZ7CY2VKJXB7K \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 4090c5e74398a0cf3b3f16355526e1fab34f8392f551a8fb7792176c2177b884

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "075067707c5099998551a2d4b1cb75682eabda6ce5f65e4285b07989f6a1f4fd",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.CC",
    "submitted_at": "2026-03-18T08:55:02Z",
    "title_canon_sha256": "2080cfc63236a0532145b829a249864535cbf7cce1405198fcdd7b3d2e91f53f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2603.17489",
    "kind": "arxiv",
    "version": 4
  }
}