Pile of gold coins

Logic Level 3

You play a game with a pile of $N$ gold coins.

You and a friend take turns removing 1, 3, or 6 coins from the pile.
The winner is the one who takes the last coin.

For the person that goes first, how many winning strategies are there for $N < 1000?$

Clarification: For $1 \leq N \leq 999$ , for how many values of $N$ can the first player develop a winning strategy?