Which US Presidents have visited India on official trips?

Dwight D Eisenhower's state visit to India in 1959 was the first by a US President to the country. Richard Nixon visited in 1969, Jimmy Carter in 1978 and George W Bush in 2006. Bill Clinton's 5-day trip to India in 2000 was the longest by a US President. Barack Obama made two official visits - in 2010 and 2015.