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harey last won the day on January 12 2017

harey had the most liked content!

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About harey

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  • Birthday February 26

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  1. Soldiers in a field

    Cannot you shorten it? - if no one else watches A nor B, remove A and B and start over (this happens if A and B are very near and all other are far away enough) - if someone else watches A and/or B, at least one is not being watched (evident; if proof needed, start with 3 and continue with recursion)
  2. Who can go the lowest?

    Bad news guys, I win: But a mathematician will not agree.
  3. Protecting Airplanes

    What kind of planes are examined? And what kind of planes are not in the sample? https://en.wikipedia.org/wiki/Abraham_Wald
  4. Binary lock

    Real life: I bought (very cheep) a 256MB extension card for a 80286. There were 8 dip switches and no manual. I do not know how many times each switch can be flipped, in any case, it is better to minimize the manipulation. Look https://en.wikipedia.org/wiki/Gray_code
  5. In Soviet Russia

    Two judges meet in Moscow, one is laughing, laughing, laughing... The second asks why. 1st judge: I heard an awfully funny joke. 2nd judge: Tell me! 1st judge: I cannot. I sentenced the man who told it to 5 years.
  6. An Associative fallacy

    My favorite one: Take the sum of all the integers. Call it S. Take the sum of even integers. That sum is S/2. Because S is infinite, S/2=S, their difference is zero. So the sum of the odd integers is zero.
  7. Roll Them Out

    I googled some definitions of "middle" and "center". If this is THE solution, than the dictionaries are pretty wrong.
  8. Roll Them Out

    Lets try it together. Hidden Content Again, to obvious to be true. But what is wrong? It can be done in a smaller chute. Sure. Applying quantum physics.
  9. A loaded coin

    One possibility: However, in theory, it can go forever..
  10. Roll Them Out

    Lets try it together. Again, to obvious to be true. But what is wrong?
  11. Magical Tennis

    A typo again...I get used. Thinking it over, it is much more complicated.
  12. Magical Tennis

    So obvious that I fear I am missing something:
  13. Prove that you solved sudoku

    @Jasen I think you got it, but SO confusing. 1) Insert the solution on small pieces of paper into the original grid, numbers down. (You better use a non-transparent paper.) 2) For each row/column/square I ask, collect your papers and show them to me in ascending order: (With the original numbers, 1-9 will be used exactly once.) 3) Put your pieces of paper back.