Fifth row edge templates

Fifth row edge templates with one stone

V-1-a

Although the next two templates look like 6th row templates with two stones, note that the 6th row stone plays no role in connecting the template to the edge. It has simply been added to show one possibility for how the 5th row red stone may be connected up. We regard these as one-stone 5th row templates.

Fifth row edge templates with two stones

V-2-b

This template is called C-5 in Seymour's book.

V-2-c

This template is called J-5 in Seymour's book.

V-2-d

The shaded cell is not part of the template. It can be occupied by Blue.

V-2-e

This template is called D-5a in Seymour's book.

V-2-f

This template is called D-5b in Seymour's book.

V-2-g

This template is called L-5a and L-5b in Seymour's book, depending on whether Red wants to connect stone A or B to the edge. The template guarantees that Red can connect, at Red's choice, either stone A or stone B to the edge. However, unlike template IV-2l, Red is not guaranteed to be able to connect them both.

Two stones on the fifth row

If Red has two stones on the fifth row with two or more empty hexes between them and the space shown below, Red can connect either one of the stones (at Red's choice) to the edge.

Red's strategy is as follows. Say Red wants to connect stone A to the edge. Then no matter where Blue plays, Red can get at least a 3rd row ladder from A. Red can then use stone B as a switchback to a 5th row ladder going in the opposite direction, which connects to A. For example:

Note that Red must choose to connect either stone A or stone B (Red cannot generally guarantee to connect them both). For example, if Blue plays here:

or here:

then Red can choose to connect A or B, but not both.