Step 4 = 16 squares
Step 15 = 225 squares
1) In the 1st step we can see, 1 square. In the 2nd, 4, and on the third one 9
So there's a sequence, 1, 4, 9
2) We can write the positions and raise them to the 2nd power we can see how it grows:
position (steps) n | 1 | 2 | 3
# squares | 1 | 4 | 9
3) We can derive a formula for that sequence:
[tex]a_n=n^2[/tex]
Following this rule, we can find that
Step 4 = 4² = 16 squares
Step 15 = 15² = 225 squares
