On the 2 x 1 grid all 7- segment digits above can be formed one at a time as seen on clocks, calculators and other digital devices.
If we are allowed to flip or rotate and overlap segments, how should these digits be configured inside the 3 x 4 grid, so we can see all of them at the same time?


Here's my solution, with the following features:

  1. Distinct 2 and 5
  2. Distinct 6 and 9
  3. Rotations only (Mirror images of numbers don't look all that nice)
  4. No upside-down digits (max. rotation 90 degrees)

enter image description here

This was way more difficult than expected. There may be other non-mirror solutions apart from this one and its symmetries, but if there are, they are few and far between.

  • $\begingroup$ Nice animations! $\endgroup$ – JS1 Jun 11 '18 at 8:45
  • $\begingroup$ there the no flipped digit solution! $\endgroup$ – TSLF Jun 11 '18 at 13:57
  • 1
    $\begingroup$ @JS1 Thanks! I made a new version now that I had time; all done with GIMP's copy-paste, rectangle select, and a paintbucket full of 36% transparent black paint :-) $\endgroup$ – Bass Jun 11 '18 at 15:49

enter image description here


0: middle row, first two columns
1: top row, first two columns
2 and 5: top two rows, third column
3: bottom two rows, second column
4: top row, last two columns
6 and 9: bottom two rows, third column
7: bottom row, first two columns
8: bottom row, last two columns
Note the last column of the middle row isn't even used.

  • $\begingroup$ full overlapping of 2 & 5 or 6 & 9 conceals the digits beneath thus we cant see $\endgroup$ – TSLF Jun 11 '18 at 4:45

enter image description here

Solution for 4 x 3 grid

5 -4 6

3 0 8

2 - 9

-7 - 1

  • $\begingroup$ The “no upside-downies” bit was just me trying to show off; my upvote is for the brilliant alternative “no-mirrored-digits” solution to the original question you had before you rotated it 90 degrees :-) $\endgroup$ – Bass Jun 11 '18 at 19:21
  • $\begingroup$ Oh, oops, it’s the OP’s self-answer. Sorry :-) $\endgroup$ – Bass Jun 11 '18 at 19:25

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