{"abstract":"Traveler-check routing numbers beginning 80 are reported malformed.","category":"Check-digit algorithms","checks":8,"contract":"US ABA routing transit number: exactly nine ASCII digits whose first two digits lie in 00-12, 21-32, 61-72 or equal 80 (else \"malformed\"). Weights 3,7,1 repeat from the left; return whether the weighted sum is a multiple of 10.","evaluation_group":"w2-check_digit_algorithms-aba-routing","failed_approach":"Allowing every prefix of 80 and above admits unassigned 81-99 prefixes.","family":"w2-check_digit_algorithms-aba-routing-electronic-prefix","id":"FA-72531","implementations":{"attempt":{"sha256":"3fd3ec8a0018bab95b4e17acfaff60d3793ab112eeb4674453f3b735dcaa4c08","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    if len(s) != 9 or not s.isascii() or not s.isdigit():\n        return 'malformed'\n    p = int(s[:2])\n    if not (0 <= p <= 12 or 21 <= p <= 32 or 61 <= p <= 72 or p >= 80):\n        return 'malformed'\n    total = sum(int(ch) * (3, 7, 1)[i % 3] for i, ch in enumerate(s))\n    return total % 10 == 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['regression [\"808489768\"]', ['808489768'], True], ['regression [\"808489769\"]', ['808489769'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"000396219\"]', ['000396219'], True], ['control [\"000396210\"]', ['000396210'], False], ['control [\"014060861\"]', ['014060861'], True], ['control [\"014060862\"]', ['014060862'], False], ['control [\"056885062\"]', ['056885062'], True]], [['regression [\"803391247\"]', ['803391247'], False], ['regression [\"800000009\"]', ['800000009'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"056885063\"]', ['056885063'], False], ['control [\"119218424\"]', ['119218424'], True], ['control [\"119218425\"]', ['119218425'], False], ['control [\"121199382\"]', ['121199382'], True], ['control [\"121199383\"]', ['121199383'], False]], [['regression [\"808489769\"]', ['808489769'], False], ['regression [\"803391246\"]', ['803391246'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"217283403\"]', ['217283403'], True], ['control [\"217283404\"]', ['217283404'], False], ['control [\"262758598\"]', ['262758598'], True], ['control [\"262758599\"]', ['262758599'], False], ['control [\"311681228\"]', ['311681228'], True]], [['regression [\"800000009\"]', ['800000009'], False], ['regression [\"808489768\"]', ['808489768'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"311681229\"]', ['311681229'], False], ['control [\"324890048\"]', ['324890048'], True], ['control [\"324890049\"]', ['324890049'], False], ['control [\"616486212\"]', ['616486212'], True], ['control [\"616486213\"]', ['616486213'], False]], [['regression [\"803391246\"]', ['803391246'], True], ['regression [\"803391247\"]', ['803391247'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"670455289\"]', ['670455289'], True], ['control [\"670455280\"]', ['670455280'], False], ['control [\"720402959\"]', ['720402959'], True], ['control [\"720402950\"]', ['720402950'], False], ['control [\"123311508\"]', ['123311508'], True]]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"ffcd20b9751895abf4a775fa38c2e4dd7fe6f75a57ab9fcb3547956d959a784d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    if len(s) != 9 or not s.isascii() or not s.isdigit():\n        return 'malformed'\n    p = int(s[:2])\n    if not (0 <= p <= 12 or 21 <= p <= 32 or 61 <= p <= 72):\n        return 'malformed'\n    total = sum(int(ch) * (3, 7, 1)[i % 3] for i, ch in enumerate(s))\n    return total % 10 == 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['regression [\"808489768\"]', ['808489768'], True], ['regression [\"808489769\"]', ['808489769'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"000396219\"]', ['000396219'], True], ['control [\"000396210\"]', ['000396210'], False], ['control [\"014060861\"]', ['014060861'], True], ['control [\"014060862\"]', ['014060862'], False], ['control [\"056885062\"]', ['056885062'], True]], [['regression [\"803391247\"]', ['803391247'], False], ['regression [\"800000009\"]', ['800000009'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"056885063\"]', ['056885063'], False], ['control [\"119218424\"]', ['119218424'], True], ['control [\"119218425\"]', ['119218425'], False], ['control [\"121199382\"]', ['121199382'], True], ['control [\"121199383\"]', ['121199383'], False]], [['regression [\"808489769\"]', ['808489769'], False], ['regression [\"803391246\"]', ['803391246'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"217283403\"]', ['217283403'], True], ['control [\"217283404\"]', ['217283404'], False], ['control [\"262758598\"]', ['262758598'], True], ['control [\"262758599\"]', ['262758599'], False], ['control [\"311681228\"]', ['311681228'], True]], [['regression [\"800000009\"]', ['800000009'], False], ['regression [\"808489768\"]', ['808489768'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"311681229\"]', ['311681229'], False], ['control [\"324890048\"]', ['324890048'], True], ['control [\"324890049\"]', ['324890049'], False], ['control [\"616486212\"]', ['616486212'], True], ['control [\"616486213\"]', ['616486213'], False]], [['regression [\"803391246\"]', ['803391246'], True], ['regression [\"803391247\"]', ['803391247'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"670455289\"]', ['670455289'], True], ['control [\"670455280\"]', ['670455280'], False], ['control [\"720402959\"]', ['720402959'], True], ['control [\"720402950\"]', ['720402950'], False], ['control [\"123311508\"]', ['123311508'], True]]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"fixed":{"sha256":"72f24617f0ee601fb7b0ca8cb44647a39af285ff67b756aa499152cd927d2595","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    if len(s) != 9 or not s.isascii() or not s.isdigit():\n        return 'malformed'\n    p = int(s[:2])\n    if not (0 <= p <= 12 or 21 <= p <= 32 or 61 <= p <= 72 or p == 80):\n        return 'malformed'\n    total = sum(int(ch) * (3, 7, 1)[i % 3] for i, ch in enumerate(s))\n    return total % 10 == 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['regression [\"808489768\"]', ['808489768'], True], ['regression [\"808489769\"]', ['808489769'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"000396219\"]', ['000396219'], True], ['control [\"000396210\"]', ['000396210'], False], ['control [\"014060861\"]', ['014060861'], True], ['control [\"014060862\"]', ['014060862'], False], ['control [\"056885062\"]', ['056885062'], True]], [['regression [\"803391247\"]', ['803391247'], False], ['regression [\"800000009\"]', ['800000009'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"056885063\"]', ['056885063'], False], ['control [\"119218424\"]', ['119218424'], True], ['control [\"119218425\"]', ['119218425'], False], ['control [\"121199382\"]', ['121199382'], True], ['control [\"121199383\"]', ['121199383'], False]], [['regression [\"808489769\"]', ['808489769'], False], ['regression [\"803391246\"]', ['803391246'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"217283403\"]', ['217283403'], True], ['control [\"217283404\"]', ['217283404'], False], ['control [\"262758598\"]', ['262758598'], True], ['control [\"262758599\"]', ['262758599'], False], ['control [\"311681228\"]', ['311681228'], True]], [['regression [\"800000009\"]', ['800000009'], False], ['regression [\"808489768\"]', ['808489768'], True], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"311681229\"]', ['311681229'], False], ['control [\"324890048\"]', ['324890048'], True], ['control [\"324890049\"]', ['324890049'], False], ['control [\"616486212\"]', ['616486212'], True], ['control [\"616486213\"]', ['616486213'], False]], [['regression [\"803391246\"]', ['803391246'], True], ['regression [\"803391247\"]', ['803391247'], False], ['partial-repair [\"811000011\"]', ['811000011'], 'malformed'], ['control [\"670455289\"]', ['670455289'], True], ['control [\"670455280\"]', ['670455280'], False], ['control [\"720402959\"]', ['720402959'], True], ['control [\"720402950\"]', ['720402950'], False], ['control [\"123311508\"]', ['123311508'], True]]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"A deterministic, bounded teaching model of the named scheme under the stated contract; not a certified validator. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w2-check_digit_algorithms-aba-routing-electronic-prefix","generated_at":"2026-09-29T14:48:39.324005+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"ACH origination checks routing numbers before transmitting a batch.","repair":"Allow p == 80 alongside the three district ranges.","root_cause":"The special prefix 80 was left out of the allowed ranges.","sha256":"81d7118a33fe68df61b43a4e69a14e9b213eab6079f739c83104ed8e9b2f9439","title":"ABA rejects the electronic prefix 80 · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":40.4,"exit_code":1,"observations":[{"actual":true,"check":"regression [\"808489768\"]","expected":true,"passed":true},{"actual":false,"check":"regression [\"808489769\"]","expected":false,"passed":true},{"actual":true,"check":"partial-repair [\"811000011\"]","expected":"malformed","passed":false},{"actual":true,"check":"control [\"000396219\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"000396210\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"014060861\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"014060862\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"056885062\"]","expected":true,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression [\\\"808489768\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"regression [\\\"808489769\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"partial-repair [\\\"811000011\\\"]\", \"actual\": true, \"expected\": \"malformed\", \"passed\": false}, {\"check\": \"control [\\\"000396219\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"000396210\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"014060861\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"014060862\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"056885062\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":37.986,"exit_code":1,"observations":[{"actual":"malformed","check":"regression [\"808489768\"]","expected":true,"passed":false},{"actual":"malformed","check":"regression [\"808489769\"]","expected":false,"passed":false},{"actual":"malformed","check":"partial-repair [\"811000011\"]","expected":"malformed","passed":true},{"actual":true,"check":"control [\"000396219\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"000396210\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"014060861\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"014060862\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"056885062\"]","expected":true,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression [\\\"808489768\\\"]\", \"actual\": \"malformed\", \"expected\": true, \"passed\": false}, {\"check\": \"regression [\\\"808489769\\\"]\", \"actual\": \"malformed\", \"expected\": false, \"passed\": false}, {\"check\": \"partial-repair [\\\"811000011\\\"]\", \"actual\": \"malformed\", \"expected\": \"malformed\", \"passed\": true}, {\"check\": \"control [\\\"000396219\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"000396210\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"014060861\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"014060862\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"056885062\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":39.854,"exit_code":0,"observations":[{"actual":true,"check":"regression [\"808489768\"]","expected":true,"passed":true},{"actual":false,"check":"regression [\"808489769\"]","expected":false,"passed":true},{"actual":"malformed","check":"partial-repair [\"811000011\"]","expected":"malformed","passed":true},{"actual":true,"check":"control [\"000396219\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"000396210\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"014060861\"]","expected":true,"passed":true},{"actual":false,"check":"control [\"014060862\"]","expected":false,"passed":true},{"actual":true,"check":"control [\"056885062\"]","expected":true,"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression [\\\"808489768\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"regression [\\\"808489769\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"partial-repair [\\\"811000011\\\"]\", \"actual\": \"malformed\", \"expected\": \"malformed\", \"passed\": true}, {\"check\": \"control [\\\"000396219\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"000396210\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"014060861\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}, {\"check\": \"control [\\\"014060862\\\"]\", \"actual\": false, \"expected\": false, \"passed\": true}, {\"check\": \"control [\\\"056885062\\\"]\", \"actual\": true, \"expected\": true, \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}