QueryBadFormed: A bad request has been sent to the endpoint: probably the SPARQL query is badly formed.

Response:
b'{\n    "exception": "Invalid SPARQL query: The second argument to the REGEX function must be a string literal (which contains the regular expression)",\n    "metadata": {\n        "line": 81,\n        "positionInLine": 11,\n        "query": "#\\nPREFIX biopax: <http://www.biopax.org/release/biopax-level3.owl#>\\nPREFIX bd: <http://www.bigdata.com/rdf#>\\nPREFIX cc: <http://creativecommons.org/ns#>\\nPREFIX datacite: <http://purl.org/spar/datacite/>\\nPREFIX dblp: <https://dblp.org/rdf/schema#>\\nPREFIX dc:    <http://purl.org/dc/elements/1.1/>\\nPREFIX dct: <http://purl.org/dc/terms/>\\nPREFIX freq:  <http://purl.org/cld/freq/>\\nPREFIX geo: <http://www.opengis.net/ont/geosparql#>\\nPREFIX geom: <http://geovocab.org/geometry#>\\nPREFIX gpml:  <http://vocabularies.wikipathways.org/gpml#>\\nPREFIX litre: <http://purl.org/spar/literal/> \\nPREFIX lgdo: <http://linkedgeodata.org/ontology/>\\nPREFIX ontolex: <http://www.w3.org/ns/lemon/ontolex#>\\nPREFIX orkgp: <http://orkg.org/orkg/predicate/>\\nPREFIX orkgc: <http://orkg.org/orkg/class/>\\nPREFIX orkgr: <http://orkg.org/orkg/resource/>\\nPREFIX owl: <http://www.w3.org/2002/07/owl#>\\nPREFIX p: <http://www.wikidata.org/prop/>\\nPREFIX pav: <http://purl.org/pav/>\\nPREFIX pq: <http://www.wikidata.org/prop/qualifier/>\\nPREFIX pqn: <http://www.wikidata.org/prop/qualifier/value-normalized/>\\nPREFIX pqv: <http://www.wikidata.org/prop/qualifier/value/>\\nPREFIX pr: <http://www.wikidata.org/prop/reference/>\\nPREFIX prn: <http://www.wikidata.org/prop/reference/value-normalized/>\\nPREFIX prov: <http://www.w3.org/ns/prov#>\\nPREFIX prv: <http://www.wikidata.org/prop/reference/value/>\\nPREFIX ps: <http://www.wikidata.org/prop/statement/>\\nPREFIX psn: <http://www.wikidata.org/prop/statement/value-normalized/>\\nPREFIX psv: <http://www.wikidata.org/prop/statement/value/>\\nPREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>\\nPREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\\nPREFIX schema: <http://schema.org/>\\nPREFIX skos: <http://www.w3.org/2004/02/skos/core#>\\nPREFIX void:  <http://rdfs.org/ns/void#>\\nPREFIX vrank: <http://purl.org/voc/vrank#>\\nPREFIX wd: <http://www.wikidata.org/entity/>\\nPREFIX wdata: <http://www.wikidata.org/wiki/Special:EntityData/>\\nPREFIX wdno: <http://www.wikidata.org/prop/novalue/>\\nPREFIX wdref: <http://www.wikidata.org/reference/>\\nPREFIX wds: <http://www.wikidata.org/entity/statement/>\\nPREFIX wdt: <http://www.wikidata.org/prop/direct/>\\nPREFIX wdtn: <http://www.wikidata.org/prop/direct-normalized/>\\nPREFIX wdv: <http://www.wikidata.org/value/>\\nPREFIX wikibase: <http://wikiba.se/ontology#>\\nPREFIX wp: <http://vocabularies.wikipathways.org/wp#>\\nPREFIX wprdf: <http://rdf.wikipathways.org/>\\nPREFIX xsd: <http://www.w3.org/2001/XMLSchema#>\\n\\nPREFIX orkgr: <http://orkg.org/orkg/resource/>\\nPREFIX orkgc: <http://orkg.org/orkg/class/>\\nPREFIX orkgp: <http://orkg.org/orkg/predicate/>\\n    \\nSELECT ?paper ?paper_title \\n       ?url ?author\\n       ?venue ?venue_label\\n       ?doi ?publication_month ?publication_year\\n       ?research_field ?research_field_label\\n       ?contribution\\nWHERE {\\n    # comment out the BINDing line to get the metadata of all papers.\\n    BIND(orkgr:R141003 AS ?paper)\\n    \\n    ?paper rdf:type orkgc:Paper;\\n           rdfs:label ?paper_title ;\\n           orkgp:hasAuthors ?authors ;\\n           orkgp:P30 ?research_field .\\n    \\n    ?research_field rdfs:label ?research_field_label .\\n    \\n    ?authors ?seq_n ?author .\\n    \\n    OPTIONAL { ?paper orkgp:P26 ?doi } .\\n    OPTIONAL { ?paper orkgp:url ?url } .\\n    OPTIONAL { ?paper orkgp:P28 ?publication_month } .\\n    OPTIONAL { ?paper orkgp:P29 ?publication_year } .\\n    OPTIONAL { ?paper orkgp:HAS_VENUE ?venue .\\n               ?venue rdfs:label ?venue_label } .\\n    OPTIONAL { ?paper orkgp:P31 ?contribution } .\\n    FILTER(REGEX(STR(?seq_n), CONCAT(STR(rdf:), \\"_\\\\\\\\d+\\")))\\n}\\nLIMIT 25",\n        "startIndex": 3494,\n        "stopIndex": 3539\n    },\n    "query": "#\\nPREFIX biopax: <http://www.biopax.org/release/biopax-level3.owl#>\\nPREFIX bd: <http://www.bigdata.com/rdf#>\\nPREFIX cc: <http://creativecommons.org/ns#>\\nPREFIX datacite: <http://purl.org/spar/datacite/>\\nPREFIX dblp: <https://dblp.org/rdf/schema#>\\nPREFIX dc:    <http://purl.org/dc/elements/1.1/>\\nPREFIX dct: <http://purl.org/dc/terms/>\\nPREFIX freq:  <http://purl.org/cld/freq/>\\nPREFIX geo: <http://www.opengis.net/ont/geosparql#>\\nPREFIX geom: <http://geovocab.org/geometry#>\\nPREFIX gpml:  <http://vocabularies.wikipathways.org/gpml#>\\nPREFIX litre: <http://purl.org/spar/literal/> \\nPREFIX lgdo: <http://linkedgeodata.org/ontology/>\\nPREFIX ontolex: <http://www.w3.org/ns/lemon/ontolex#>\\nPREFIX orkgp: <http://orkg.org/orkg/predicate/>\\nPREFIX orkgc: <http://orkg.org/orkg/class/>\\nPREFIX orkgr: <http://orkg.org/orkg/resource/>\\nPREFIX owl: <http://www.w3.org/2002/07/owl#>\\nPREFIX p: <http://www.wikidata.org/prop/>\\nPREFIX pav: <http://purl.org/pav/>\\nPREFIX pq: <http://www.wikidata.org/prop/qualifier/>\\nPREFIX pqn: <http://www.wikidata.org/prop/qualifier/value-normalized/>\\nPREFIX pqv: <http://www.wikidata.org/prop/qualifier/value/>\\nPREFIX pr: <http://www.wikidata.org/prop/reference/>\\nPREFIX prn: <http://www.wikidata.org/prop/reference/value-normalized/>\\nPREFIX prov: <http://www.w3.org/ns/prov#>\\nPREFIX prv: <http://www.wikidata.org/prop/reference/value/>\\nPREFIX ps: <http://www.wikidata.org/prop/statement/>\\nPREFIX psn: <http://www.wikidata.org/prop/statement/value-normalized/>\\nPREFIX psv: <http://www.wikidata.org/prop/statement/value/>\\nPREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>\\nPREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\\nPREFIX schema: <http://schema.org/>\\nPREFIX skos: <http://www.w3.org/2004/02/skos/core#>\\nPREFIX void:  <http://rdfs.org/ns/void#>\\nPREFIX vrank: <http://purl.org/voc/vrank#>\\nPREFIX wd: <http://www.wikidata.org/entity/>\\nPREFIX wdata: <http://www.wikidata.org/wiki/Special:EntityData/>\\nPREFIX wdno: <http://www.wikidata.org/prop/novalue/>\\nPREFIX wdref: <http://www.wikidata.org/reference/>\\nPREFIX wds: <http://www.wikidata.org/entity/statement/>\\nPREFIX wdt: <http://www.wikidata.org/prop/direct/>\\nPREFIX wdtn: <http://www.wikidata.org/prop/direct-normalized/>\\nPREFIX wdv: <http://www.wikidata.org/value/>\\nPREFIX wikibase: <http://wikiba.se/ontology#>\\nPREFIX wp: <http://vocabularies.wikipathways.org/wp#>\\nPREFIX wprdf: <http://rdf.wikipathways.org/>\\nPREFIX xsd: <http://www.w3.org/2001/XMLSchema#>\\n\\nPREFIX orkgr: <http://orkg.org/orkg/resource/>\\nPREFIX orkgc: <http://orkg.org/orkg/class/>\\nPREFIX orkgp: <http://orkg.org/orkg/predicate/>\\n    \\nSELECT ?paper ?paper_title \\n       ?url ?author\\n       ?venue ?venue_label\\n       ?doi ?publication_month ?publication_year\\n       ?research_field ?research_field_label\\n       ?contribution\\nWHERE {\\n    # comment out the BINDing line to get the metadata of all papers.\\n    BIND(orkgr:R141003 AS ?paper)\\n    \\n    ?paper rdf:type orkgc:Paper;\\n           rdfs:label ?paper_title ;\\n           orkgp:hasAuthors ?authors ;\\n           orkgp:P30 ?research_field .\\n    \\n    ?research_field rdfs:label ?research_field_label .\\n    \\n    ?authors ?seq_n ?author .\\n    \\n    OPTIONAL { ?paper orkgp:P26 ?doi } .\\n    OPTIONAL { ?paper orkgp:url ?url } .\\n    OPTIONAL { ?paper orkgp:P28 ?publication_month } .\\n    OPTIONAL { ?paper orkgp:P29 ?publication_year } .\\n    OPTIONAL { ?paper orkgp:HAS_VENUE ?venue .\\n               ?venue rdfs:label ?venue_label } .\\n    OPTIONAL { ?paper orkgp:P31 ?contribution } .\\n    FILTER(REGEX(STR(?seq_n), CONCAT(STR(rdf:), \\"_\\\\\\\\d+\\")))\\n}\\nLIMIT 25",\n    "resultsize": 0,\n    "status": "ERROR",\n    "time": {\n        "computeResult": 1,\n        "total": 1\n    }\n}'