Stairways and Blocks

The problem

A student diagrammed a stairway using squares to represent blocks that could be used to build stairways of different heights. After the first drawing the student though it would be better if the staircase went up and down. Therefore, drew the second drawing. Satisfied that was better continued with the pattern and drew the third drawing.

image staircases

  1. Each row is made with blocks. How many blocks are in each row?
  1. Each complete stair case is made with a certain number of blocks. How many blocks are needed to build the staircase in drawing 3?
  1. If the number of blocks in the bottom row was known, how could the number of blocks needed to build a double sided staircase be determined?