Edge template VI1a

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This template is the first one stone 6th row template for which a proof has been handwritten.

Elimination of irrelevant Blue moves

Red has a couple of direct threats to connect, using smaller templates. Blue must play in the carrier of these threats in order to counter them. To prevent Red from connecting Blue must play in the intersection of Red's threats carriers.

edge template IV1a

edge template IV1b

Using the parallel ladder trick

6 moves can furthermore be discarded thanks to the Parallel ladder trick. Of course, symmetry will cut our work in half!

We can dispose of 3 moves on the left (and, using mirror symmetry, the corresponding 3 moves on the right), as follows:

132546

At this point, we can use the Parallel ladder trick as follows:

7561324

Remaining possibilities for Blue

Blue's first move must be one of the following:

Specific defence

For the moves that intersect all the carriers, Red has to find specific answers. Let's deal with the remaining intrusions!

One remaining intrusion on the first row (stub)

The other remaining intrusion on the first row

The remaining intrusion on the second row

The remaining intrusion on the third row

The remaining intrusion on the fourth row

Red should move here:

Elimination of irrelevant Blue moves

This gives Red several immediate threats: From III1a:

From III1a again:

From III1b :

From IV1a:

From IV1b:

The intersection of all of these leaves:

abcdefghijklmn1234567

Specific defence

So we must deal with each of these responses. (Which will not be too hard!)

Bg4
1243

And now either

21

or

625431
Bg5
abcdefghijklmn123456721

Threatening:

abcdefghijklmn12345674
abcdefghijklmn12345674
abcdefghijklmn12345674

So the only hope for Blue lies in the intersection of the threats, Be5, but it is unsufficient:

abcdefghijklmn123456712846357
Bg6
2431

3 could be played at + with the same effect; in any case now either

21

or

625431
Be7
246351
Bg7
28347615

The remaining intrusion on the fifth row

First establish a double ladder on the right.

17382546

Then use Tom's move:

53142