Pith Number

pith:2QXR5FUW

pith:2010:2QXR5FUWO4BENBR4FE7Q2ZIDUJ

not attested not anchored not stored refs pending

Matrix sparsification and the sparse null space problem

Lee-Ad Gottlieb, Tyler Neylon

arxiv:1008.1498 v1 · 2010-08-09 · cs.CC · math.NA

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{2QXR5FUWO4BENBR4FE7Q2ZIDUJ}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

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.

Receipt and verification

First computed	2026-05-18T04:42:24.108068Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

d42f1e9696770246863c293f0d6503a25a1cba33cd0e963545f3f30278b34b12

Aliases

arxiv: 1008.1498 · arxiv_version: 1008.1498v1 · doi: 10.48550/arxiv.1008.1498 · pith_short_12: 2QXR5FUWO4BE · pith_short_16: 2QXR5FUWO4BENBR4 · pith_short_8: 2QXR5FUW

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/2QXR5FUWO4BENBR4FE7Q2ZIDUJ \
  | 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: d42f1e9696770246863c293f0d6503a25a1cba33cd0e963545f3f30278b34b12

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "57fc790746f0a15931728417453ae3542233ac3fbdd9978c8c9172c77280b2d5",
    "cross_cats_sorted": [
      "math.NA"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.CC",
    "submitted_at": "2010-08-09T13:14:58Z",
    "title_canon_sha256": "112e90a71ee29687869a369161d195eb56dba263926dfd09a147e724de5c1679"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1008.1498",
    "kind": "arxiv",
    "version": 1
  }
}