CREATE TABLE table_78737 ("President" TEXT, "Date of inauguration" TEXT, "Age at inauguration" TEXT, "End of term" TEXT, "Length of retirement" TEXT, "Lifespan" TEXT)

What is the Date of inauguration of the President with an Age at inauguration of 73years, 262days?
SELECT "Date of inauguration" FROM table_78737 WHERE "Age at inauguration" = '73years, 262days'
SELECT "Date of inauguration" FROM "table_78737" WHERE "Age at inauguration" = '73years, 262days'