Question: Who is the paternal grandfather of Janusz Iii Of Masovia?

Context paragraphs:
title: Siemowit III, Duke of Masovia
paragraph_text: Siemowit III of Masovia( his name also rendered Ziemowit; – 1381) was a prince of Masovia and a co-regent( with his brother Casimir I of Warsaw) of the lands of Warsaw, Czersk, Rawa, Gostynin and other parts of Masovia.
title: Konrad III Rudy
paragraph_text: Konrad III the Red (pl: " Konrad III Rudy"; 1447/48 – 28 October 1503), was a Polish prince member of the House of Piast in the Masovian branch. He was a duke of Czersk, Liw, Warsaw, Nur, Łomża, Ciechanów, Różan, Zakroczym and Wyszogród during 1454-1471 jointly with his brothers (under regency until 1462), Duke of Płock, Wizna, Płońsk and Zawkrze during 1462-1471, and after the division of the paternal domains in 1471, sole ruler over Czersk and Liw, over Wyszogród during 1474-1489 and again in 1495, over Zakroczym since 1484, over Nur since 1488 and over Warsaw since 1489. He was the third son of Bolesław IV of Warsaw and Barbara Olelkovna of Slutsk-Kapy, a Lithuanian princess, (granddaughter of Vladimir Olgerdovich). The premature death of his two older brothers during 1453-1454 left him as the eldest surviving son of his family.
title: Zbigniew Oleśnicki (primate of Poland)
paragraph_text: Zbigniew Oleśnicki( 1430 – 1493), nephew of Cardinal Zbigniew Oleśnicki, was a Roman Catholic clergyman and Polish politician. He served as crown deputy chancellor from 1472, bishop of Kuyavia from 1472, and bishop of Gniezno and primate of Poland from 12 October 1481. He was born, about 1430, into the influential Debno noble family; he was the son of Marshal of the Kingdom of Poland Jan Oleśnicki, and the nephew of Zbigniew Cardinal Oleśnicki of Kraków During the absence of King Casimir IV Jagiellon he was deputized in several state matters including dealing with the Prussians; however, by the end of Casimirs reign their relationship had soured, probably due to a rivalry with Fryderyk Jagiellończyk, the Bishop of Kraków and Casimir's relative. After the death of Casimir, he was a strong supporter for the election of Janusz III of Masovia to be the new king. He died on 2 February 1493 in Łowicz and was buried in the Cathedral of Gniezno, where his tomb was built with red marble by Veit Stoss.
title: Sophia of Masovia
paragraph_text: Sophia of Masovia( 1497/1498- before 11 March 1543) was a Princess of Masovia, daughter of Konrad III Rudy, Duke of Masovia and his wife Anna Radziwiłł. She was a member of the House of Piast. On 17 September 1520 in Warsaw, Sophia was married by proxy to Stephen VII Báthory. On 17 January 1521, Sophia and her entourage went to Hungary, where in February there was a formal marriage. The couple had three children: Anna, Stephen and Klara; however, other sources claim that Klara was the couple's only child. Klara was engaged to Carl, Duke of Münsterberg, but died in 1535, before the marriage took place. After the death of Stephen in 1530, Sophia was married to Croatian magnate Louis Pekry. Sophia's second marriage was childless. She then died sometime before 11 March 1543. Sophia had three siblings: Stanislaus I of Masovia, Janusz III of Masovia and Anna of Masovia, both her brothers died childless and so Anna and Sophia were the last Masovian Piasts. Soon after Janusz's death, the Duchy of Masovia was annexed into the kingdom of Poland, despite resistance from some of the Masovian nobility. They tried to retain their independence and argued that the Duchy should be inherited by the female relatives( such as Anna or Sophia). The Polish king refused to recognize their demands. Anna was made titular Duchess of Masovia.
title: Margaret of Masovia
paragraph_text: Margaret of Masovia( before 1358 – 14 May 1388/4 April 1396) was Duchess of Pomerania and Brzeg, by her marriages to Casimir IV, Duke of Pomerania and then to Henryk VIII with a Scar. She was a member of the House of Piast. Margaret was a daughter of Siemowit III of Masovia and his wife Euphemia of Opawa. Her paternal grandparents were Trojden I of Masovia and his wife Maria, daughter of Yuri I of Galicia and Euphemia of Kuyavia.
title: Janusz III of Masovia
paragraph_text: Janusz III of Masovia (pl: "Janusz III mazowiecki"; ca. 27 September 1502 – 9/10 March 1526), was a Polish prince member of the House of Piast in the Masovian branch. He was a Duke of Czersk, Warsaw, Liw, Zakroczym and Nur during 1503-1524 (under regency until 1518) jointly with his brother, and sole ruler during 1524-1526 as the last male member of the Masovian Piasts. He was the second son of Konrad III the Red and his third wife Anna, a daughter of Mikolaj Radziwiłł "the Old", Voivod of Vilnius and the first Grand Chancellor of Lithuania.
title: Kaya Alp
paragraph_text: Kaya Alp was, according to Ottoman tradition, the son of Kızıl Buğa and the father of Suleyman Shah, who was, in turn, the grandfather of Ertuğrul, and the great grandfather of the Ottoman Empire founder, Osman I.
title: Anna of Masovia
paragraph_text: Anna of Masovia (c. 1498 – after 26 January 1557 in Jaroslaw) was Princess of Mazovia and a member of the House of Piast. She was the last representative of the line of Masovian-Piast. She was the second daughter of Konrad III of Masovia and Anna Radziwiłł. She was a sister of Dukes Janusz III of Masovia and Stanislaus of Masovia, and Sophia, who married Stephen VII Báthory.
title: Siemowit I of Masovia
paragraph_text: Siemowit I of Masovia( c. 1224/28 – 23 June 1262), was a Polish prince member of the House of Piast, Duke of Czersk during 1247- 1248, Duke of Masovia( except Dobrzy ń) during 1248- 1262, ruler over Sieradz during 1259- 1260. He was the sixth son of Konrad I of Masovia and his wife Agafia of Rus. He was named after his older brother Siemowit, who died young in 1224.
title: Gaudemunda of Lithuania
paragraph_text: Gaudemunda Sophia of Lithuania( also Gaudimantė; c. 1260 – 1288/1313) was the daughter of Traidenis, Grand Duke of Lithuania( c. 1270 – 1282). In 1279 she married Duke of Masovia Bolesław II( c. 1254–1313) of the Piast dynasty. He was the son of Ziemowit I, Prince of Masovia, and Pereyaslava, daughter of Daniel of Galicia of the Rurik dynasty. Her husband united the Duchy of Masovia and then divided it between their sons, who were:

Reasoning steps:
Janusz III of Masovia father Konrad III the Red
Konrad III the Red father Bolesław IV of Warsaw

Answer: spans: Bolesław IV of Warsaw