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Pith Number

pith:IUX7QQWU

pith:2005:IUX7QQWUVD2RS2TA3FEUPNO5PO
not attested not anchored not stored refs pending

The problem of distinguishing between a center and a focus for nilpotent and degenerate analytic systems

H\'ector Giacomini, Jaume Gin\'e, Jaume Llibre

arxiv:math/0506116 v2 · 2005-06-07 · math.DS · math.CA

Add to your LaTeX paper
\usepackage{pith}
\pithnumber{IUX7QQWUVD2RS2TA3FEUPNO5PO}

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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.
Receipt and verification
First computed 2026-05-18T00:44:18.913344Z
Builder pith-number-builder-2026-05-17-v1
Signature Pith Ed25519 (pith-v1-2026-05) · public key
Schema pith-number/v1.0

Canonical hash

452ff842d4a8f5196a60d94947b5dd7b8296cff6141b32b2773b35b196aa1ca5

Aliases

arxiv: math/0506116 · arxiv_version: math/0506116v2 · doi: 10.48550/arxiv.math/0506116 · pith_short_12: IUX7QQWUVD2R · pith_short_16: IUX7QQWUVD2RS2TA · pith_short_8: IUX7QQWU
Agent API
Verify this Pith Number yourself
curl -sH 'Accept: application/ld+json' https://pith.science/pith/IUX7QQWUVD2RS2TA3FEUPNO5PO \
  | 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: 452ff842d4a8f5196a60d94947b5dd7b8296cff6141b32b2773b35b196aa1ca5
Canonical record JSON
{
  "metadata": {
    "abstract_canon_sha256": "6c5f70db6dda116fc648fa68650f9b8ae973ce41e61654e05b25cd52ea75e8fb",
    "cross_cats_sorted": [
      "math.CA"
    ],
    "license": "",
    "primary_cat": "math.DS",
    "submitted_at": "2005-06-07T14:26:28Z",
    "title_canon_sha256": "a523d6310c12c204e9ef5249bca1fc7f4ddf3ab62c1c40eeb5bef28793375c54"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/0506116",
    "kind": "arxiv",
    "version": 2
  }
}