The digits in the grey cells are part of a domino of which the sum of both digits adds to a prime number.
Solve online in Penpa+ (thx Nick Smirnov!)
Solution code: 1) The missing digits, row by row. 2) The number of horizontally placed dominos, row by row.
on 9. October 2022, 07:56 by Richard
Added link and tag for online solving. Thx Nick!
on 3. October 2022, 10:48 by Nick Smirnov
Penpa:
https://tinyurl.com/2pn2jcgd
on 5. September 2012, 19:01 by cornuto
Tolles 2-Sterne-Rätsel, super konstruiert.
on 2. June 2012, 14:54 by Skinny Norris
Super! Vielen Dank! :)
on 1. June 2012, 17:27 by Statistica
Klasse Idee, das Thema schön ausgereizt.
on 1. June 2012, 12:50 by ibag
Naja, ich hatte es ja auch schon seit ein paar Wochen. ;-)
on 1. June 2012, 12:37 by Luigi
@ibag: Du hast tatsächlich nur 0,01 Sekunden gebraucht... Oha! Da werden neue Uvo Maßstäbe gesetzt... ;-))