1 n-th term of a geometric sequence or geometric progression with initial value and common ratio 2 Time needed for two workers to do a job together (group work) (given individual capacities) 3 n-th square pyramidal number or pyramid number 4 n-th term of arithmetic progression (AP) or arithmetic sequence (given common difference) 5 Initial term of arithmetic progression or arithmetic sequence (given n-th term and common difference) 6 Common difference of arithmetic progression or arithmetic sequence (given first and n-th terms) 7 Arithmetic series (given initial term,n-th term,arithmetic progression,arithmetic sequence) 8 Arithmetic series (given initial term,common difference,arithmetic progression,arithmetic sequence) 9 Initial term of arithmetic progression or arithmetic sequence (given n-th term,arithmetic series) 10 Number of terms of arithmetic progression or arithmetic sequence (given terms,arithmetic series) 11 n-th term of arithmetic progression or arithmetic sequence (given arithmetic series,first term) 12 Initial term of arithmetic progression,arithmetic sequence (given common difference,arithmetic series) 13 Common difference of arithmetic progression,arithmetic sequence (given initial term and arithmetic series) 14 Sum of the first n cubes 15 Factorial of a non-negative integer n 16 nth root of a positive real number 17 Logarithm of a positive real number x with respect to base b 18 Common logarithm of a positive real number 19 n-th term of arithmtic series (given n, m-th term and initial term) 20 Common difference of arithmtic progression(given m,n, m-th and n-th terms) 21 Natural exponential function 22 The determinant of a 2-by-2 matrix 23 The determinant of a 3-by-3 matrix 