Walter -

Thanks for the thoughts and good questions on further rule changes in Pente. Three changes have been proposed. They are called D-pente, G-pente, and S-pente. The games actually exist on www.gamerz.net but no tourneys have been run with them, as far as I know. I think we're just kind of waiting for all of the openings to be exhausted with the current rules, which we are close to doing now.

The letters before the name of Pente is the first letter of the first or last name of the people who proposed them. D-pente was proposed by Don Banks of Canada and S-pente was proposed by Oleg Stepanov of Russia, both top players. G-pente was proposed by yours truly.

Here's the rules for D-pente:
1. Player 1's (white) first move is to center.
2. Player 2 now makes 3 consecutive moves while alternating colors. (black-white-black) There is no restriction on the placement.
3. Player 1 (white) now must decide whether to keep the white stones or swap sides and play the black stones.

Regardless of what the original player 1 (OP1) chooses to do, it is white's move. So if OP1 chooses to swap, he is now black and it is his opponent's move. If he did not swap, then he is white and it is his move. The strategy for OP2 is to make the position as EVEN as possible after making the 3 consecutive moves, which makes the opening full of possibilities and much more interesting.

This is a very good variation that virtually guarantees that neither side will get much of an advantage if the players are reasonably skilled. The only problem is that some players will not like to swap sides and it is a little tricky programatically. But it is easy enough that most people would understand it.

I will briefly mention S-pente. This is a complicated swapping version that I have not taken the time to understand even though I've looked for a while at the rules. It involves possible swapping on the 3rd, 4th, and 5th move so that there can be 0 thru 3 swaps in a game. I don't think there's much chance that very many players will like this because it is too difficult to understand.

Of course my favorite is G-pente since I proposed it! It is EXACTLY like Pente with the current opening restriction except that there is only ONE further restriction on player 1's 2nd move, that is:
Player 1's 2nd move must be at least 3 intersections from his opening move AND it can NOT be in a straight line horizontally or vertically from his opening move either 3 or 4 intersections away. In other words using the coordinates here at Brain King, white can also NOT move to F10, G10, N10, O10, K6, K7, K13, and K14 on his 2nd move.

The reason for this is that virtually ALL of player 1's advantage in Pente with the current restriction is as a result of player 1 making a 'straight line' move from his opening move. It is my opinion that this will even things up for the foreseeable future.

BUT...that said, even with G-pente, it IS possible in 5-10 years (or perhaps less) that one side or the other will be analyzed by top players to have a substantial advantage once again. If that happens, there would probably be no choice but to go to a swap variation.

In proposing G-pente, I have only done a moderate amount of analysis on it and could not come up with anything conclusive for either side, which is what I wanted. I also haven't heard any other strong opinion one way or another on it from top players, although it hasn't been discussed much.

If you want to see the 3 games in program form, Mark Mammel has some software that you can download and that plays all 3 of them on his site. You can find a link to his site at Dweebo's Stone Games at www.pente.org. There is a place on the left side of the main menu for links.

A couple of last things. I think you were confused by what Dmitri King meant by running out of room on a 13x13 board. We would NEVER attempt to imply that the board would fill completely up with stones, even on a 13x13 board. That simply wouldn't happen if the players were trying to win. What he meant is that on a 13x13 board, you would hit the edge of the board quite frequently, ESPECIALLY in Keryo-Pente. You wouldn't notice it so much playing lesser players, but since you're a good player, if you consistently played other good players, you'd notice it quite frequently.

In Pente with the current opening restriction on a 19x19 board, on a rare occassion, say 1 in 25-50 games amongst top players, the edge of the board will be a factor. In Keryo Pente, I would say that the edge of the board would be a factor in 1 in 10-15 games in the same situation. This is after having played several games of it at www.pente.org.

As far as the 100x100 or infintiy board thing, I'm not sure why anyone would want that and it would be potentially VERY problematic to display on someone's screen. But from a purist mathematical perspective, I can understand what you are alluding to there.



Gary