Khaled and Wilma were asked to find an explicit formula for the sequence 1\,,\,3\,,\,9\,,\,27,...1,3,9,27,.. .1, comma, 3, comma, 9, comma, 27, comma, point, point, point, where the first term should be f(1)f(1)f, left parenthesis, 1, right parenthesis. Khaled said the formula is f(n)=1\cdot3^{{n-1}}f(n)=1⋅3 n−1 f, left parenthesis, n, right parenthesis, equals, 1, dot, 3, start superscript, n, minus, 1, end superscript, and Wilma said the formula is f(n)=1\cdot3^{{n}}f(n)=1⋅3 n f, left parenthesis, n, right parenthesis, equals, 1, dot, 3, start superscript, n, end superscript. Which one of them is right?