Q: Why was this mod copy and pasted from Emmote's version?
A: They no longer play the game, and have granted permission to others to update it in their stead (see: https://mods.factorio.com/mod/InfiniteWorkerRobotCapacity_Research/discussion/5ef9cc43936a68d808d43a67)

Q: What is the formula for reasearch cost?
A: This is it: (1.5^(L-1)*200). It was written by Emmote, if you feel it needs to be re-balanced, feel free to reach out.