The sequence for the given situation is:

y (number of people who know about the soft opening
y0: number of people who know about the soft opening at day 0
As each person will tell 2 people about the soft opening you multiply the number of people of previous dat (y(x-1)) by 2 and add to it the initial number of people (1).
Then, the data in the table is find using the formula of the sequence above:

You get the next table: