question: Who is the paternal grandfather of Túathal Mac Máele-Brigte?
context: [["Abd al-Muttalib", ["Abd al- Muttalib Shaybah ibn Hashim( c. 497 \u2013 578) was the grandfather of Islamic prophet Muhammad."]], ["Muiredach mac Brain (died 818)", ["Muiredach mac Brain (died 818) was a King of Leinster of the U\u00ed Muiredaig sept of the U\u00ed D\u00fanlainge branch of the Laigin.", "This sept had their royal seat at Maistiu (Mullaghmast) in South Kildare.", "He was the son of Bran Ardchenn mac Muiredaig (died 795), a previous king.", "He ruled from 805 to 806 and again from 808 to 818.", "Though not listed in the king list in the \"Book of Leinster\", he is mentioned in the Irish annals.", "He is given the title\n\"leth-ri\" (one of two kings) at his death in 818 (\"Annals of Ulster\") and ruled in conjunction with Muiredach mac Ruadrach (died 829) of the U\u00ed F\u00e1el\u00e1in sept.", "In 795 his father, Bran, had been assassinated by his successor F\u00ednsnechta Cethardec mac Cellaig (died 808) of the U\u00ed D\u00fanchada sept as a direct challenge to the high-king.", "In 805 F\u00ednsnechta was deposed by the high king \u00c1ed Oirdnide (died 819) of the Cen\u00e9l nE\u00f3gain who installed Muiredach mac Brain and Muiredach mac Ruadrach as kings.", "Finsnechta took refuge with Muirgius mac Tommaltaig (died 815), the King of Connacht who then aided him in recovering his throne in 806.", "Upon the death of Finsnechta, Muiredach mac Brain and Muiredach mac Ruadrach were returned to rule.", "In 814 a battle is recorded between the U\u00ed Cheinnselaig of south Leinster and the sons of Bran.", "The battle was won by the sons of Bran, probably Muiredach and his brother Cellach mac Brain (died 834).", "Upon the death of Muiredach mac Brain, Muiredach mac Ruadrach became sole ruler.", "Muiredach's sons, Tuathal mac Muiredaig (died 854) and D\u00fanlaing mac Muiredaig (died 869) were also kings of Leinster.", "Another son Art\u00far mac Muiredaig (died 847) was king of western Liffey, Iarthair Liffey."]], ["John Westley", ["Rev. John Westley( 1636 \u2013 78) was an English nonconformist minister.", "He was the grandfather of John Wesley( founder of Methodism)."]], ["Kaya Alp", ["Kaya Alp was, according to Ottoman tradition, the son of K\u0131z\u0131l Bu\u011fa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertu\u011frul, and the great grandfather of the Ottoman Empire founder, Osman I."]], ["Lyon Cohen", ["Lyon Cohen( 1868\u20131937) was a Polish- born Canadian businessman and a philanthropist.", "He was the grandfather of singer/ poet Leonard Cohen."]], ["Guillaume Wittouck", ["Guillaume Wittouck( 1749- 1829) was a Belgian lawyer and High Magistrate.", "He was the Grandfather of industrialist Paul Wittouck."]], ["Fujiwara no Nagara", [", also known as Fujiwara no Nagayoshi, was a Japanese statesman, courtier and politician of the early Heian period.", "He was the grandfather of Emperor Y\u014dzei."]], ["Henry Bryant (naturalist)", ["Henry Bryant( May 12, 1820 \u2013 February 2, 1867) was an American physician and naturalist.", "He was the grandfather of Henry Bryant Bigelow."]], ["T\u00faathal mac M\u00e1ele-Brigte", ["Tuathal mac M\u00e1ele-Brigte (died 854) was a King of Leinster of the U\u00ed Muiredaig sept of the U\u00ed D\u00fanlainge branch of the Laigin.", "This sept had their royal seat at Maistiu (Mullaghmast) in South Kildare.", "He was possibly the son of Muiredach mac Brain (died 818), a previous king.", "However he is known as the son of M\u00e1el-Brigte in the annals, which person's identity is unknown.", "The succession of kings in Leinster is difficult to follow in his time.", "The king lists in the \"Book of Leinster\"", "have Tuathal succeed his cousin Lorc\u00e1n mac Cellaig and Tuathal is given a reign of three years giving a reign of 851-854.", "Byrne suggests that the root of this apparent confusion lay in the fact that the U\u00ed D\u00fanlainge kings exercised little real authority due to the aggressions of their western neighbour Cerball mac D\u00fanlainge (died 888), King of Osraige.", "Cerball, while unable to install himself as king of Leinster, was able to prevent any rival king exercising real power there.", "In his death obit in the annals in 854 it states that he was wickedly killed by his own kinsmen.", "He is only accorded the title of King of the U\u00ed D\u00fanlainge."]], ["Prithvipati Shah", ["Prithvipati Shah( ?\u20131716) was the king of the Gorkha Kingdom in the Indian subcontinent, present- day Nepal.", "He was the grandfather of Nara Bhupal Shah."]]]
supporting_facts: [["T\u00faathal mac M\u00e1ele-Brigte", 2], ["Muiredach mac Brain (died 818)", 2]]
evidences: [["Tuathal mac M\u00e1ele-Brigte", "father", "Muiredach mac Brain"], ["Muiredach mac Brain", "father", "Bran Ardchenn"]]
answer: Bran Ardchenn