Sequences and Series

Question

1. What would the dimensions be for n=3?

2. Draw the shape for n=4. Insert your drawing below.

3. Write a rule for the sequence, with n for the input and the number of cubes for the output.

4. How many cubes in the shape for n=20?

Answer 1

The sequence appears to be a_n = (n+2)²(n+1) for integer n≥0...you should be able to draw the required figure and substitute 20 for n in the above formula.