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Naccel 2 -- post #4x (triplet and pair)

Posted By: Nack Ballard
Date: Monday, 18 January 2010, at 3:30 p.m.

For reference, the bgonline material on Naccel 2 (so far) is:

This is a bonus post, written between post #4 and post #5. It contains illustrations and basic explanations of two basic squads: the "triplet" (review) and the "pair" (new).

As always, (Naccel) point numbers are labeled in white and Super (Super-point) numbers in black.

Triplet (two examples)7 and 1

A "triplet" can appear on any even-numbered point. To count a triplet, simply divide its point number by 2.

Above, the far-side triplet is on the (Naccel) 14pt and therefore counts 7. The near-side triplet is on the (Naccel) 2pt and therefore counts 1. For another example, this triplet (tenth diagram) is on the -2pt and therefore counts -1.

(By dividing by 2, you are in essence counting the number of two-point (third-quadrant) steps to the Naccel 0pt. The 14pt triplet counts 7 because it takes 14/2 = 7 two-point steps to journey it to the 0pt.)

[Scholarly note: A more obscure method is to count the nearest Super twice and the second-nearest Super once. Hence, in the above cases, 2 + 2 + 3 = 7, and 0 + 0 + 1 = 1. In essence, you are shifting two checkers 2 pips each and the other checker 4 pips in the opposite direction and counting the occupied Supers.]

Pair (two examples)5 and -1

A "pair" can appear on any third point of the board; either on a Super (though then it is commonly counted as twice the Super) or, as here, in the middle of any field. A "field," or sometimes called "squad field," is the five-point area composed of all the points in a quadrant minus its Super.

There are two ways you can count a pair. The first way (related to the divide-triplet-by-two logic) is: Divide the point number by 3. Above, the far-side pair sits on the (Naccel) 15pt and therefore counts 5. The near-side pair sits on the -3pt (read as the "minus 3 point" or "neg 3 point") and therefore counts -1.

(By dividing by 3, you are in essence counting the number of 3-pip or half-quadrant steps to the Naccel 0pt. The 15pt pair counts 5 because it takes 15/3 = 5 half quadrant steps to journey it to the 0pt.)

The second way to count a pair you may find even easier: Sum the Supers flanking it (because if you like you can equally shift one checker to each). The far-side pair sits between S2 and S3 and therefore counts 2 + 3 = 5. The near-side pair sits between S-1 (the minus 1 Super, the bearoff tray) and S0 and therefore counts -1 + 0 = -1.

While these methods are great for helping you to build and remember counts for larger groups, you will no longer need to apply a method at all to a pair or triplet (or any other squad or formation) for which you've already learned the count. Once you know, for example, that the far side pair is 5, and the far side triplet in the previous diagram is 7, a method to achieve that count becomes academic. Nothing beats an instant count.

9(3)

In this position, White has opened with 42 and Blue has replied with double 5s. Both players made an inside point.

Blue has a basic squad in each of his near-side quadrants. His pair counts -1 and his triplet counts +1. These two squads offset/reflect around n0, and this near-side formation (no matter how many checkers are on the irrelevant 0pt) is a standard poof; a count of zero.

Blue's entire count is 6 (for two on S3), plus 3(3) for the midpoint checkers, making 9(3).

Let's repeat the diagram, and this time count for White:
11(5)

White has an even more basic poof on her near side. (If you haven't seen it before, review the explanation of the fourth diagram here.) The points with two checkers on either side of her 0pt are symmetrical. So, White's entire count is 6 (for two on S3), plus 5(5) for five on her midpoint, making 11(5).

The difference between White's 11(5) and Blue's 9(3) is 2(2). That's how far Blue is ahead in the race after playing his double 5s.

Nack

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