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Everything posted by CaptainEd

  1. Killer quickie

  2. Coin hunt

  3. Poisoned Needles

    Is it possible that the needles are actually...
  4. Ants on an icosagon

    Rodocmac, thank you, but I’ll pass. I’ve posted “oops” enough for now :-)
  5. Ants on an icosagon

    Thanks, rodocmac Ants on octahedron Once again attempting to count unique permutations
  6. Strange math problem

    Cute, Bonanova! Good solve Molly Mae!
  7. Ants on an icosagon

    Ants on octahedron Once again attempting to count unique permutations
  8. Random passengers

    Please disregard this post. I now understand that 50/50 does not mean probability 1.
  9. Ants on an icosagon

    Rocdocmac, we are clearly well matched: I had a misenumeration and a miscount, and I’ll raise you my typographical error.
  10. Ants on an icosagon

    Oops can’t count
  11. Ants on an icosagon

    Ants on cube Now I see it would be easier if I counted permutations.
  12. Shortest set of lines in a square, revisited

    Nice job, Plasmid
  13. Dumb robot

    Plasmid, that’s an impressively simple solution to all the n=3 mazes! Of course, the 5x5 solution is impressive, too! Harey, this is a very interesting puzzle.
  14. Ants on an icosagon

    tetrahedron: success only if no two ants arrive at same cell
  15. Ants on an icosagon

    Woops, I did not consider the possibility of two ants arriving at the same vertex through different paths...
  16. Ants on an icosagon

    (a) and (b), haven't done (c) yet: I assume a trial consists of all ants moving from one vertex to one other vertex. (In other words, we aren't asked about the probability of them never colliding, no matter how far they wander)). icosagon tetrahedron
  17. Five rings

    interesting question.
  18. Five rings

    Here’s a degenerate answer
  19. Shortest set of lines in a square, revisited

    Ok, Another try:
  20. Random passengers

    Kay_Kay, I don’t follow the argument.
  21. Shortest set of lines in a square, revisited

    Oh well, here’s an upper bound, as it’s an easy answer:
  22. Dumb robot

    Thanks for pruning unnecessary instructions.
  23. Dumb robot

    Harey, I’m with you: there’s a crazy number of possible mazes just in n=3. I think I’ve got them covered:
  24. Dumb robot

    Harey, can we assume as Molly Mae did, that there is no maze, but only a simple path? I assumed otherwise, that it can be a maze, so I imagined a figure H, with only two cells with cement (top center and bottom center).
  25. Dumb robot

    I must be wrong, imagine a capital H in a 3x3 grid. How do I get to the crossbar? Any Down or Up would take me to the bottom or top of the left vertical bar, with no way to stop in the middle. So, now I guess that each instruction moves the robots either 0 or 1 spaces.