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plasmid last won the day on March 8 2017

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About plasmid

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  1. Coin hunt

    So if you have N coins to choose from, instead of needing log2N coins to specify its position you can guarantee that you only need (log2N / 2) + 1 flips. Nice move to halve the upper limit, but with 1000 coins you could still be in for an hour of nyan. That might work well for random configurations ... the math to figure out how many flips it would take on average would be difficult and maybe worth being its own question. But the worst case scenario if the bazillion coin is in the middle, the left half is all heads, and the right half is all tails would be a real pain.
  2. Coin hunt

  3. Baggage on a conveyor belt

    SMH, continuing from that last line of formula... Edit: Nevermind, I think you have to calculate the value over the range of integration for the numerator and denominator separately, I don't think you can just divide through like that. And after looking it up, those limits go to zero so I've got an indeterminate 0/0 still.
  4. Baggage on a conveyor belt

    Does not compute when I try a Poisson distribution. I might be doing something wrong.
  5. Coin hunt

    This one
  6. Coin hunt

    Flipping the same coin twice would be indistinguishable from not flipping it at all to your buddy. So you would just be exposing yourself to more nyaning without accomplishing anything.
  7. Coin hunt

    It looks like harey and aiemdao have sort of similar strategies, and that the number of coins flipped would be up to log base 2 of the total number of coins. With harey's answer it could be less for certain numbers of coins in play, but not for all. But if there are more than even a mere 32 coins, then you could be in for up to a solid hour of nyan-ing which might not be worth a bazillion bucks. Try for an approach with less, especially when the number of coins gets large.
  8. Coin hunt

    I have a rare coin that’s worth a bazillion dollars and I’ll give you and a buddy a chance to win it. I’ll bring you (but not your buddy yet) into a room where I have a bunch of coins lined up in a row, probably randomly distributed between being heads up and tails up, and I’ll tell you which coin among those is the bazillion dollar coin. Then you’ll exit the room and your buddy will come in through another entrance (so you can’t communicate after I tell you which is the bazillion dollar coin) and tell me which coin to give to the two of you. That wouldn't be a very fair game, so you can also tell me to flip whichever coins you want before you leave the room and your buddy comes in. (I’m flipping them myself to make sure you don’t send codes with subtle placement of the coins or such tomfoolery.) But you have to watch 10 minutes of Nyan Cat for every coin I flip so you want to minimize the number of flips lest you go insane. I’m not saying beforehand how many coins will be in the room, and you only get one minute to tell your buddy a strategy (just words that can be spoken in under a minute, no written cheat sheets) before it’s time to play the game. Clock starts now. (I would credit the source of where I heard the original form of this puzzle that I'm modifying, but I can't remember the source any more.)
  9. Traffic jams

    This might count as an ah-hah if it's true.
  10. Obtuse triangles in a circle

    Not an answer, but a description of a potential approach and what would still be needed to make it work since this has gone for a while without being cracked.
  11. Pairing the points

    Probably not what you have in mind, but I realized part of my previous answer was superfluous so this is a little more elegant and gets rid of some hand waving.
  12. Pairing the points

  13. I’m not a gardener

    Right on, Cygnet! Hopefully things make sense to readers with that answer in mind, but I'll go ahead and say what I was thinking for each of the clues.
  14. I’m not a gardener

    None of the above, I’m afraid. A barrel (particularly if it’s a wine barrel) could fit most of the clues except for the oddly even adulating when not dispensing slight, and for wine I would have called the roses red and white instead of pink and white while for this riddle it definitely should be pink and white. I can say that thirteen is not involved in this riddle; the oddly even among the 14 is among a natural group of 14. And a bringer of good luck is involved, but I’m looking for something that can do everything from grow the pink and white roses, adulate or dispense slight, and fit the last two lines.