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  1. Yesterday
  2. Cubicle Stack #2

    By the way, Thalia ...
  3. Waiting, again II

  4. Waiting, again II

    <spoiler> Before any coin is flipped, there are an even number of heads. This is the Even state; if a Head is flipped, we go to the Odd state. Whenever we flip a Tail in Even state, we are back to zero which is Even state. If we get a Tail in Odd state, we win! If we get a Head in Odd state, we go to Even state. If we get a tail in Even state, we go to Odd state. </spoiler>
  5. Waiting, again II

    Not sure if it was clear that the run of odd number of heads are contiguous, as in the example, or if I'm misunderstanding your algorithm. Can you add some words here and there?
  6. Peter and Paul, who are neighbors, each threw a party last Friday. Bad scheduling, to be sure, but that's life. All 100 of their friends were sent invitations to both parties. When guests arrived, the happy sounds of the those already present could be heard through the two open doors, and the old phrase "the more the merrier" figured in their choice of party to attend: If at any point there were a people present at Peter's party and b people present at Paul's party, the next guest would join Peter with probability a/(a+b) and join Paul with probability b/(a+b). When the first guest arrived only the two hosts were present, so that choice was a tossup. But the symmetry was then broken. What is the expected number of guests at the less-attended party?
  7. Waiting, again

    And Children's Activities had some cool features on the last page - cartoon, riddle or puzzle - as I recall.
  8. Whodunit?

    Yes, there can be a "bonus" row that contains 4 trees. Here's an adequate proof of the killer:
  9. Cubicle Stack #2

    Nevermind the CEX numbers. I really need to find a cube I can hold...
  10. Cubicle Stack #2

    I see what you mean about CEX although I'm not sure how to show that with the numbering system. That throws a wrench in my counting. . .
  11. Waiting, again II

  12. Jelly beans join the clean plate club

    Aw man, I was so confident I'd finally solved one of Bonanova's legendary puzzles. A start on thinking:
  13. Largest unit sphere

    Nice, thanks!
  14. Cubicle Stack #2

    So 6/7 in the last post and check CEX?
  15. Waiting, again

    Gardner sets high standard in many ways. I was a child reading Childrens Activities and a few years later I was enjoying hexaflexagons and later mathematical games. I was kneeling behind you in worship. i enjoy the puzzles here, and sometimes I don’t understand something that is obvious to anyone else. I think I may have a touch of ambiguity flu. Keep on puzzling, Bonanova!
  16. Last week
  17. Whodunit?

    My guess:
  18. Waiting, again

    @CaptainEd - OMG no. Awhile ago I next-to-worshiped Martin Gardner (who wrote the math games column in Sci American for so many years) because he worded his puzzles perfectly, simply and clearly. His, unlike mine, (try tho I may) never needed editing. When I wrap prose around mine to make them perhaps interesting or, sometimes, to camouflage the solution, stuff gets added that has often has to be clarified later. My bad on this one.
  19. Whodunit?

    Clarification: Dick asserts that he had been out running, and that one of his three brothers has just lied. Inspector just called in and needs a final answer ... Fame awaits the brave.
  20. Jelly beans join the clean plate club

    Sorry guys, "fuller" should have read "at least as full." Examples always help, so here is an example. a b c 7 9 12 <- 14 2 12 -----> 2 2 24 -> 0 4 24 So { 7 9 12 } is a starting point where a plate can be emptied. Can any { a < b < c } lead to an empty plate? A Yes answer needs proof; a No answer just needs a counter example.
  21. Jelly beans join the clean plate club

    I have a doubt to confirm.
  22. Cubicle Stack #2

    Think I found one of the 2 I changed from correct to incorrect. But I think that would leave one of these as still wrong though I can't figure out which. . .
  23. Whodunit?

    Oops, you're right! Sorry!
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