Need expression to animate slider between integers and hold for specific duration

I know this sounds random, but i need an expression to animate a slider control between two integers in increasing value for one second, and then to hold for 4 seconds at that value, and then increase again by one over one second and then hold for 4 seconds.

For example value of 1 between 0 and 4 seconds, then linerally animate between 1 and 2 between 4 and 5 seconds, then hold at 2 between 5 and 9 seconds, then animate to 3 between 9 and 10 seconds.

I thought about using a loop but was unsure about how to best write the code. Any suggestions? Thanks in advance.

Mike