oldies by goldies ... thanks!
And pretty impressive for 10 year-old code, all I had to do in order to make it run in 2010b was to edit line 27 from:
The plastic "perspico" was a huge hit in Romania when I was a kid. Numbers came in two colours (blue/red for odd/even) and on the back it had 6 (or maybe 9?) different output solutions to reach. (the normal 1-15 was called "horizontal", then "vertical", "spiral", "random" (a jumble everyone avoided), "total 30" and "impossible" which was 15:-1:1 , of course unreachable due to its opposite parity.
Thanks, this made my day :-)