If the series were 9, 54, 243, 972 (instead of given 927), 3645, ..... Then the series can be explained as follows 9*((3^0)*1), 9*((3^1)*2), 9*((3^2)*3), 9*((3^3)*4), 9*((3^4)*5) So finally answer = 9*((3^5)*6) = 13,122.