Quote:
... The diamond shape letters very scare and expensive these days ...
Any thoughts on why they were folded into a diamond shape?
One is so accustomed to seeing rectangles.
I could see folding a letter into a triangle.
I am willing to posit that the same piece of paper, folded into a triangle of the
same area as the respective rectangle (eg, the height of the triangle would be greater than the height of the rectangle, so there is no advantage conferred by simply being 'smaller'), would better resist damage.
The reason, of course, would be that three corners are fewer than four and would, therefor, each be made from more paper.
even as each was formed into a narrower angle.Don't wait to be convinced: I cannot prove the Five Color Map Theorem, either.
But a diamond shape?
Cheers,
/s/ ikeyPikey