A recent thread about points of inflection reminded me of a function I encountered when I was a math student.
The function had many points of inflection but it also had points, which I presume are also called inflection points, where the gradient was infinite (i.e tending to a vertical rather than horizontal line on an x,y graph).
I remember the graph looking like a staircase with rounded edges but I have completely forgotten what the function was. It's possible I have not remembered it correctly due to it being so long ago.
Can anyone tell me what this function was or give me a similar function?