Recently new publications about tetrads were presented.
In none of them I got credit for my tetrads published by Martin Gardner.
For example the smallest polyomino tetrad with no hole. (More details are written in question 9.)
I am glad that George Sicherman made changes to his website [7] after a hint from my friend William Walkington. Thanks to both.
It seems that the internet replaces real life. Things that cannot be found in the web cease to exist.
On the other hand, I understand that for structures which were initially created before computers, but which can be found by computers today, it seems no longer necessary to mention the initial author.
During my life I worked on tetrads from time to time.
Therefore I would like to obtain a small part of recognition for my previous work on tetrad constructions.
Other reasons:
I am retired and have some free time for writing.
I want to tell my own Tetrad story and demonstrate my way of solving this problem.
I want to make experiences with vector graphics (Inkscape, GeoGebra)
The title of this website pays homage to Scott Kim's wonderful slideshow. [11]