Project Euler Forum

I'd appreciate some clarification on Problem 692 (View Problem), Siegbert and Jo. The second rule of the game is: "In each of the following turns the current player must take at least one pebble and at most twice the amount of pebbles taken by the previous player."

So the current player may take from 1 to 2n stones, inclusive. But is n the number of pebbles taken by the previous player on the immediately preceding turn, or the total number of pebbles the previous player has taken over the course of the game?

It is the number of pebbles taken by the previous player on the immediately preceding turn.