Eye and eyesight training, seeing speed

Short screen flash with a number
-should not be a problem for the eyes, white screen to whit screen with a black number might be best
-Being able to put in a random number (from 1 to 1000000000 for example) and any hundreds of a second. And increasing speed when needed, possible.

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Being able to draw a full image, while only being able
to look at that image for a certain short period amount of time.
-any time and increasing speed when needed, possible.
-And from simple images to complicated images.

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By Jef Koelewijn
From South-Holland, The Netherlands
30-05-2019