Edge template IV2l - Revision history

Selinger: Converted to new hexboard diagrams

2020-12-10T16:49:44Z

Converted to new hexboard diagrams

Selinger: Since the analysis of connecting two stones is now simpler than that of connecting one, deleted the latter.

2020-06-22T02:45:02Z

Since the analysis of connecting two stones is now simpler than that of connecting one, deleted the latter.

Selinger: Simplified the analysis, thanks to Eric Demer.

2020-06-22T02:40:02Z

Simplified the analysis, thanks to Eric Demer.

Selinger: Copy-editing.

2020-06-20T15:12:59Z

Copy-editing.

Selinger: Added a detailed discussion of the fact that Red can connect both stones.

2020-06-20T15:09:10Z

Added a detailed discussion of the fact that Red can connect both stones.

Selinger: Grammar and punctuation.

2020-06-15T04:49:11Z

Grammar and punctuation.

Selinger: Added disambiguation, since IV2I and IV2l look the same in sans serif fonts.

2020-06-15T04:37:35Z

Added disambiguation, since IV2I and IV2l look the same in sans serif fonts.

Selinger: Grammar

2020-06-13T05:18:28Z

Grammar

Richyfourtytwo: Created page with "The template: (From: [http://www.drking.org.uk/hexagons/hex/tem..."

2016-05-16T19:57:14Z

Created page with "The template: <hexboard size="4x6" coords="hide" contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3" /> (From: [http://www.drking.org.uk/hexagons/hex/tem..."

New page

The template:

<hexboard size="4x6"
coords="hide"
contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3"
/>

(From: [http://www.drking.org.uk/hexagons/hex/templates.html www.drking.org.uk])

Red can choose which of the two stones to connect to the bottom. Below, it is assumed that Red picks the stone on the right hand side.

Red has three threats:

<hexboard size="4x6"
coords="hide"
contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E +:e2 E +:f2 E *:a3 R 1:e3 E +:d4 E +:e4"
/>

<hexboard size="4x6"
coords="hide"
contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E +:d2 R 1:e2 E +:f2 E *:a3 E +:c3 E +:d3 E +:e3 E +:f3 E +:b4 E +:c4 E +:e4 E +:f4"
/>

using [[Defending_against_intrusions_in_template_1-IIIb|II-1-b]]

and

<hexboard size="4x6"
coords="hide"
contents="E *:a1 E *:b1 E *:c1 R d1 E +:e1 R f1 E *:a2 E *:b2 E +:c2 R 1:d2 E +:e2 E *:a3 E +:b3 E +:c3 E +:d3 E +:a4 E +:b4 E +:c4 E +:d4"
/>

using the [[ziggurat]]

For a blocking attempt Blue has to play on one the only overlapping field:

<hexboard size="4x6"
coords="hide"
contents="E *:a1 E *:b1 E *:c1 R d1 E +:e1 R f1 E *:a2 E *:b2 B 1:e2 R 2:f2 E *:a3 R 6:c3 E +:d3 R 4:e3 B 5:d4 B 3:e4"
/>

Red 6 is connected to the bottom and can be connected to the top right by one of the fields marked with +.

== See also ==

[[category:edge templates]]

@@ Line 1: / Line 1: @@
 ''This page is about edge template IV2l (four two ell). There is also an [[edge template IV2i]] (four two eye).''
-The template:
+Template IV2-l is a 4th row [[edge template]] with 2 stones.
 <hexboard size="4x6"
     coords="hide"
     contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3"
     />
 (From: [http://www.drking.org.uk/hexagons/hex/templates.html www.drking.org.uk])
 Red can connect both of the two stones to the bottom, i.e., Red does not have to choose which of the two stones to connect. To show this, we consider every possible intrusion into the template. Since the template is symmetric, we only need to consider intrusions by Blue into the right-hand side of the template (or on the center line).
@@ Line 15: / Line 19: @@
 <hexboard size="4x6"
-    coords="show"
+    coords="bottom right"
     contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 E +:e1 +:e2 +:e3 +:e4 +:f2 +:f3 +:f4 R 2:d3"
     />
@@ Line 24: / Line 30: @@
 <hexboard size="4x6"
-    coords="show"
+    coords="bottom right"
     contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 E +:d3 +:d4 R 2:c3"
     />
 [[category:edge templates]]

@@ Line 49: / Line 49: @@
 To show that Red can, in fact, connect both stones to the bottom, we consider every possible intrusion into the template. Since the template is symmetric, we only need to consider intrusions by Blue into the right-hand side of the template (or on the center line).
-If Blue plays in any of the cells marked "+", Red responds at d2 and is connected by a [[ziggurat]].
+If Blue plays in any of the cells marked "+", Red can respond at d3.
 <hexboard size="4x6"
     coords="show"
-    contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 E +:f2 +:f3 +:f4 +:e3 +:e4 R 2:d2"
+    contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 E +:e1 +:e2 +:e3 +:e4 +:f2 +:f3 +:f4 R 2:d3"
     />
-If Blue plays 1.e1, Red responds with 2.d3 and is connected by two copies of [[edge template IV2d]]:
+Then d1 is connected by [[edge template IV2d]] and f1 connects via e1 or e2 or [[edge template III2e]]. Since Blue has so far played only one of the cells marked "+", at least two of those three are still available. Also, since d3 [[captured cell|captures]] c4 and d4, the overlap between edge template IV2d and edge template III2e does not matter.
-<hexboard size="4x6"
+If Blue plays d3 or d4, Red can respond at c3.  d1 connects via two bridges, and f1 connects via e1 or e3.  Since Blue has so far played only one of the cells marked "+", two of d3, d4, e4 are still available, which is sufficient to connect e3 to the edge.
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:e1 R 2:d3"
-   />
-−
-If Blue plays 1.e2, Red responds with 2.f2:
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:e2 R 2:f2"
-   />
-−
-If Blue now plays 3.e4, the game proceeds as shown above. If Blue plays 3.e1, Red responds with 4.c3. In all other cases, Red responds with 4.e1.
-−
-If Blue plays 1.d3, Red responds with 2.e1 and is connected via [[edge template IV2a]]:
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:e3 R 2:e1"
-   />
-−
-If Blue plays 1.d4, Red responds with 2.e1:
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:d4 R 2:e1"
-   />
-−
-Now if Blue plays outside the area marked "+" in the next figure, Red connects with c3:
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:d4 R 2:e1 E +:b4 +:c2 +:c3 +:c4 +:d2"
-   />
-−
-If Blue plays outside the area marked "+" in the next figure, Red proceeds as in defending [[edge template IV2a]] (since Blue only has one stone in the template ''and it is Red's turn''):
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B 1:d4 R 2:e1 E +:c4 +:d2 +:d3 +:e2 +:e3 +:e4 +:f2 +:f3 +:f4"
-   />
-−
-That leaves only two possible plays for Blue, at d2 and c4. They are easily dealt with:
-−
-<hexboard size="4x6"
-   coords="show"
-   contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B d4 R e1 B 3:d2 R 4:c3 B 5:c2 R 6:e3"
-   />
 <hexboard size="4x6"
     coords="show"
-    contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B d4 R e1 B 3:c4 R 4:b3 B 5:c2 R 6:f3 B 7:f2 R 8:d3"
+    contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 E +:d3 +:d4 R 2:c3"
     />

@@ Line 46: / Line 46: @@
 == Connecting both stones ==
 If Blue plays in any of the cells marked "+", Red responds at d2 and is connected by a [[ziggurat]].
@@ Line 77: / Line 79: @@
     />
-If Blue plays 1.d4, Red also responds with 2.e1:
+If Blue plays 1.d4, Red responds with 2.e1:
 <hexboard size="4x6"
@@ Line 109: / Line 111: @@
     contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E *:a3 B d4 R e1 B 3:c4 R 4:b3 B 5:c2 R 6:f3 B 7:f2 R 8:d3"
     />
 == See also ==
 [[category:edge templates]]

← Older revision		Revision as of 04:37, 15 June 2020
Line 1:		Line 1:
		+	''This page is about edge template IV2l (four two ell). There is also an [[edge template IV2i]] (four two eye).''
		+
	The template:		The template:

← Older revision		Revision as of 05:18, 13 June 2020
Line 34:		Line 34:
	using the [[ziggurat]]		using the [[ziggurat]]

−	For a blocking attempt Blue has to play on ~~one~~ the only overlapping field:	+	For a blocking attempt, Blue has to play on the only overlapping field:

@@ Line 10: / Line 10: @@
 (From: [http://www.drking.org.uk/hexagons/hex/templates.html www.drking.org.uk])
-Red can choose which of the two stones to connect to the bottom. Below, it is assumed that Red picks the stone on the right hand side.
+== Choosing which stone to connect ==
 Red has three threats. The first one uses bridges.
@@ Line 42: / Line 43: @@
     />
 Red 6 is connected to the bottom and can be connected to the top right by one of the fields marked with +.
 == See also ==
 [[category:edge templates]]

@@ Line 13: / Line 13: @@
-Red has three threats:
+Red has three threats. The first one uses bridges.
 <hexboard size="4x6"
@@ Line 19: / Line 19: @@
     contents="E *:a1 E *:b1 E *:c1 R d1 R f1 E *:a2 E *:b2 E +:e2 E +:f2 E *:a3 R 1:e3 E +:d4 E +:e4"
     />
 <hexboard size="4x6"
@@ Line 25: / Line 27: @@
     />
-using [[Defending_against_intrusions_in_template_1-IIIb|II-1-b]]
+The third one uses the [[ziggurat]].
-−
-and
 <hexboard size="4x6"
@@ Line 34: / Line 34: @@
     />
 For a blocking attempt, Blue has to play on the only overlapping field:
 <hexboard size="4x6"