Pith Number

pith:QHAN2WUM

pith:2009:QHAN2WUMREPN3INASNUOBCSS4C

not attested not anchored not stored refs pending

On the indefinite Helmholtz equation: complex stretched absorbing boundary layers, iterative analysis, and preconditioning

Bram Reps, Hisham bin Zubair, Wim Vanroose

arxiv:0912.0180 v2 · 2009-12-01 · cs.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{QHAN2WUMREPN3INASNUOBCSS4C}

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	2026-05-18T04:42:03.934676Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

81c0dd5a8c891edda1a09368e08a52e0a272bdf1e145657a3bb6028e9fcb546f

Aliases

arxiv: 0912.0180 · arxiv_version: 0912.0180v2 · doi: 10.48550/arxiv.0912.0180 · pith_short_12: QHAN2WUMREPN · pith_short_16: QHAN2WUMREPN3INA · pith_short_8: QHAN2WUM

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/QHAN2WUMREPN3INASNUOBCSS4C \
  | 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: 81c0dd5a8c891edda1a09368e08a52e0a272bdf1e145657a3bb6028e9fcb546f

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "e8d8a319d199fccb64ee0015d0efd447d5c0d26f01a4f230550780e596b86d60",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.NA",
    "submitted_at": "2009-12-01T15:15:44Z",
    "title_canon_sha256": "00fdc485f228702d72b6b5fa38f3ac3d923db333751d60dd96a61daead95e80b"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0912.0180",
    "kind": "arxiv",
    "version": 2
  }
}