Seiza bench.

Nobody fell for my ruse, I see.  Good on you.  Needless to say, what I was doing there was trying to get someone to corroborate my math.

My math says A=113 degrees, B=77 degrees, A to B equals 6.65".  It's a little imprecise, but I didn't need precision, angle-wise, anyway.  I built a seiza bench using those numbers; what you see there, in the diagram, is a leg, two legs, really.

I don't know if I mentioned this: I'm meditating again.  As I'm not nearly as flexible as I used to be, I couldn't get into even half-lotus without discomfort. Then, reading around, I come across this story about a guy who blew his knee to crud attempting half-lotus.  Just attempting.  So, I decided seiza was probably the way to go.

It's working well, this seiza bench.  The way I figure it, I'll gradually grow accustomed to the sharp angles of my knees, and possibly one day remove the bench altogether.