Life In 19x19

In a club game tonight I got into a situation where I tried to play a move in sente that would let my stones connect, but my opponent ignored and kept me cut. I had read that black could do no better than ko in the corner.

Click Here To Show Diagram Code

[go]$$Wm1 Anything but ko?
$$ | X . . . . O O O
$$ | O X X . X . X .
$$ | O O O O . X . .
$$ | . X X O O . X .
$$ | . . . X O O X .
$$ | . 1 X . X O . .
$$ | . . . . . . . .
$$ | . . . . . . . .
$$ -----------------[/go]

I was able to kill the corner, but my opponent felt he could've lived if he'd played better. Was I wrong? Does black have a way to live in the corner without an unfavorable ko? Or even is there a way for white to kill without the ko? Looking at varitions on my own I don't think a ko is avoidable.

Click Here To Show Diagram Code

[go]$$Wm1 This is the ko I foresaw...
$$ | X . . . . O O O
$$ | O X X . X . X .
$$ | O O O O . X . .
$$ | . X X O O . X .
$$ | . 3 . X O O X .
$$ | . 1 X C X O . .
$$ | . 2 . 4 5 6 . .
$$ | . . . . . . . .
$$ -----------------[/go]

For those wondering how this developed. This was the general idea (I don't remember everything about the surrounding stones perfectly, but the corner situation is accurate.)

Is that a ko?

Click Here To Show Diagram Code

[go]$$Wm1 This is the ko I foresaw...
$$ | X . . . . O O O
$$ | O X X . X . X .
$$ | O O O O . X . .
$$ | . X X O O . X .
$$ | b 3 . X O O X .
$$ | . 1 X 6 X O . .
$$ | . 2 . 4 5 a . .
$$ | . . . . . . . .
$$ -----------------[/go]

Click Here To Show Diagram Code

[go]$$Wm1 This is the ko I foresaw...
$$ | X . . . . O O O
$$ | O X X . X . X .
$$ | O O O O . X . .
$$ | 9 X X O O . X .
$$ | 8 3 0 X O O X .
$$ | . 1 X 6 X O . .
$$ | . 2 . 4 5 7 . .
$$ | . . . . . . . .
$$ -----------------[/go]

Click Here To Show Diagram Code

[go]$$Wm1 This is the ko I foresaw...
$$ | X . . . . O O O
$$ | O X X . X . X .
$$ | O O O O . X . .
$$ | O X X O O . X .
$$ | 3 O X X O O X .
$$ | 1 O X X X X O . .
$$ | 2 X X . X O O . .
$$ | . . . 4 . . . .
$$ -----------------[/go]

Uh... First, your last diagram is not of the same board position. Second, white can play like this:

is a mistake.

Thanks Bill.

Yes, is clearly a mistake. Without that move black is just dead.

It does look like an interesting position can come out of this. By avoiding kos I think both sides could achieve life.

The White play at F1 is a waste of time if White is going to connect at F2. White plays the ko.

However, instead of D2, doesn't Black just play A4? How will White prevent Black from living?

Edit: Oops, wrong again. A4 looks like ko also after A5.