How can I make a graphical plot of a sequence of numbers from the standard input?

If have a long text file and I want to display all the lines in which a given pattern occurs, I do:

grep -n form innsmouth.txt | cut -d : -f1

Now, I have a sequence of numbers (one number per line)

I would like to make a 2D graphical representation with the occurrence on the x-axis and the line number on the y-axis. How can I achieve this?