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  1. Past hour
  2. Cubicle Stack #2

    Nevermind the CEX numbers. I really need to find a cube I can hold...
  3. Today
  4. 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. . .
  5. Waiting, again II

    <spoiler> As you said, it IS easy, after a while of thinking I’m clueless. My solution is a recursive evaluation, based on a two/state machine. The two states are based on parity of H seen so far, “Even” and “odd” In even state H -> 1/2 (1+ odd) T -> 1/2 (1+ even) To summarise: Even = 1/2(1+odd) + 1/2(1+even) Similarly, Odd = 1/2(1+even) + 1/2 = 1 + even /2 Substitute odd into even Even = 1/2 + 1/2(1+even/2) + 1/2 +even/2 = 3/2 + 3even/4 Solve for even 1/4 even = 3/2 Even =6 </spoiler>
  6. 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:
  7. Largest unit sphere

    Nice, thanks!
  8. Cubicle Stack #2

    So 6/7 in the last post and check CEX?
  9. 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!
  10. Yesterday
  11. Whodunit?

    My guess:
  12. 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.
  13. 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.
  14. 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.
  15. Jelly beans join the clean plate club

    I have a doubt to confirm.
  16. 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. . .
  17. Whodunit?

    Oops, you're right! Sorry!
  18. Whodunit?

  19. Whodunit?

    I think if we're getting into the analysis of the logical AND, we could say that any of them are telling falsehoods. The trees, for example, could have been pear trees instead, so the entire statement would evaluate false. I doubt that's the intention of the puzzle.
  20. Largest unit sphere

    Question: the process shown demonstrates a local maximum for the function, but is there a way to prove that (for instance) at n=1000 it doesn't suddenly reach a new maximum? (I guess what I'm trying to say is, is there a proof, or is the solution presented here just process of elimination?)
  21. Whodunit?

  22. Last week
  23. I'm Back

    I never participated in the Brian Dennis series, but I do remember them. Welcome back!
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