In which year range did Mehmed the Conqueror gained power as the sultan of the Ottoman Empire ?
SELECT ?value1 ?value2 WHERE { wd:Q34503 p:P39 ?s . ?s ps:P39 wd:Q15315411 . ?s pq:P582 ?value1 . ?s pq:P580 ?value2 }
mehmed the conqueror: Q34503 sultan of the ottoman empire: Q15315411