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| XGID=-----bE-C--BbD---d-cA-b-b-:0:0:1:55:0:0:3:0:10 | |||||
51$-65R-54P-32S-55P-52P-22@-55 | |||||
I would try 20/15 13/3 8/3. What is that, 55M?
You're very close. It's underlined M.
By the previous tutorial, the Mayfair Split referred to a move that split a back checker (which is actually meant to refer to any far side portion), came down, and made an inside point. It did not specify whether the (source of the) point-making checkers came from the outer board or from the inner board.
In other words, once upon a time, your move [which one might notate 20/15 13/8 8/3(2) or even 20/15 13/8 8/3 8/3 to more clearly show in which area each of the four portions (sub-moves) are played], was indeed nactated with a plain, non-underlined M.
Nactation has evolved. The tri-areal (three-area) doublet letters G, Y and M were overworked, and tricky to remember. Now F has been added to the tri-areal group, and they have been reorganized into a 3 x 4 matrix (while retaining as much of the original meanings as possible). I think you will find section 16 of the tutorial interesting reading.
Another way to nactate your 20/15 13/8 8/3(2) play is to use assumption, with "5." According to the current tutorial, it means "I'm moving a checker to [its final destination of] the 15pt and you figure out the rest." That assumptive choice seems shaky, though, as 20/15 13/8 6/1(2) is a conceivable alternative.
Stick's suggestion of 13/3(2) [which, one might think of as 13/8(2) 8/3(2)], has the more familiar Nactation of O (Outer), because it plays in only two areas (Down and Jump). Another example, shown in diagram #13 of the tutorial, is 66O, which plays two 6s down (13/7(2)) and jumps two 6s over the bar (8/2(2)). That is, Stick's 55O very similarly brings two 5s down (13/8(2)) and jumps two checkers (that happen to be the same two checkers) with two 5s over the bar (8/3(2)).
[As explained in section 15, if you play in the same two areas as a BEACON letter, but instead of a 2:2 ratio it is 3:1 or 1:3, underline or dot (add a period to) the letter, respectively. With that (plus S and Z are preferred replacements for B and B.), you now know how to nactate with all eighteen bi-areal families!]
13/3(2) can also be (and usually is) nactated P (Point).
Nack