numstep.bsky.social

26 August 2026 08:22

Here's today's #Numstep #Puzzle Can you solve it? #logic #math Full printable here: app.box.com/s/z2trdbrgoz...

numstep.bsky.social

24 August 2026 10:20

Here is today's #numstep. Can you solve it? #logic #puzzles

Harald Hanche-Olsen 🇳🇴

hagra.no

26 July 2026 12:33

In this case, we can always apply a projective transformation to move all the intersection points away from the line at infinity, meaning no parallel pairs in the Euclidean plane. So there should be only three distinct cases.

Harald Hanche-Olsen 🇳🇴

hagra.no

26 July 2026 12:33

It's interesting to consider this in the projective plane instead. There will be fewer different configurations, but how many? For example, the top two are now the same.

David K Butler

davidkbutler.bsky.social

25 July 2026 08:27

Suppose a collection of lines passes through the points P and Q but no points other than P and Q are shared between any two lines. A line through P but not Q and a line through Q but not P can’t meet in another point so they’d have to be parallel. Any other line would have to pass through P and Q.