1. Subscribersonhouse
    Fast and Curious
    slatington, pa, usa
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    29 Jun '14 15:56
    Originally posted by Agerg
    Well if we're allowed logs then (as per the wikipedia article for this puzzle) we have
    -sqrt(4)log(log(sqrt( ... n times ... (sqrt(4) ... ))/log(4))/log(4)
    = -2 log(2^(-n)log(4)/log(4))/log(4)
    = 2n log(2)/log(4) = 2n * .5 = n 🙂

    and so

    -sqrt(4)(log(log(sqrt(4))/log(4)))/log(4) = 1
    -sqrt(4)(log(log(sqrt(sqrt(4)))/log(4)))/log(4) = 2
    -sqrt(4)(log(log(sqrt(sqrt(sqrt(4))))/log(4)))/log(4) = 3
    .
    .
    .
    .
    Can you imagine what that solution would look like for 1,000,000,000,000🙂
  2. Standard memberAgerg
    The 'edit'or
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    29 Jun '14 17:061 edit
    Originally posted by sonhouse
    How does 0! = 1? I thought factorial for zero would be zero, zero times one should be zero and one times zero should be zero.
    How does 0! = 1? I thought factorial for zero would be zero, zero times one should be zero and one times zero should be zero.
    It is defined to be 1. A nice explanation of why can be found at:

    http://mathforum.org/library/drmath/view/57128.html


    Can you imagine what that solution would look like for 1,000,000,000,000🙂
    Heh...I'll be honest and say that I cannot imagine what the solution would look like!
  3. Joined
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    29 Jun '14 19:285 edits
    Hmm, following the pattern and using exactly 4 4's

    "-(log(log(" & { "sqrt(" x 10^12} & "4)" & { " )" x 10^12} & "/log(4))/log(4/sqrt(4))"

    Where & means concatenate the strings, and { string x n} means repeat string n times, I think that is 7000000000032 characters

    according to http://amazingbibletimeline.com/bible_questions/q10_bible_facts_statistics/
    there are 3,116,480 letters in a king james bible, so we could print the sum in the equivalent of 2,246,124 bibles. If each book was 4 cm thick, the stack of books would be 90km high.

    Factorial n is the number of ways of arranging n different things, so the way I always think about it is that there is 1 way of having absolutely nothing.
  4. Standard memberforkedknight
    Defend the Universe
    127.0.0.1
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    01 Jul '14 17:07
    Originally posted by AThousandYoung
    4^4+4/4

    PEMDAS

    No Parentheses
    Exponenent is next...

    256+4/4

    Then Multiplication and Division...

    256+1

    Then Addition and Subtraction...

    257

    Parentheses are unnecessary to avoid ambiguity. Order of Operations...
    Thank you.

    Parenthesis do not exist only for entering things into a calculator
  5. Standard memberSoothfast
    0,1,1,2,3,5,8,13,21,
    Planet Rain
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    06 Aug '14 03:181 edit
    Originally posted by sonhouse
    Can you imagine what that solution would look like for 1,000,000,000,000🙂
    Aw, that's easy:

    (4/.4)^(4!/sqrt(4))

    EDIT: I typed .4 as 0.4 originally, so…fixed!
  6. Standard memberSoothfast
    0,1,1,2,3,5,8,13,21,
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    06 Aug '14 03:28
    Wait a minute, couldn't 1000 more easily be rendered thus:

    4(4^4)-4!

    Or has this been done already?
  7. santa cruz, ca.
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    07 Aug '14 20:20
    Originally posted by Soothfast
    Wait a minute, couldn't 1000 more easily be rendered thus:

    4(4^4)-4!

    Or has this been done already?
    simple is more appealing and using the log function can lead to some very ugly solutions
    I like your solution
  8. Joined
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    17 Aug '14 21:46
    But the log function works mindlessly for any integer, that was the point of it, not to give the most elegant answer for all integers, but to prove an answer exists for *every* integer.
  9. santa cruz, ca.
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    19 Aug '14 02:42
    Originally posted by iamatiger
    But the log function works mindlessly for any integer, that was the point of it, not to give the most elegant answer for all integers, but to prove an answer exists for *every* integer.
    gotcha
  10. Joined
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    26 Aug '14 17:10
    I think that I have got a long way towards 100. If anybody is interested I'll go and find my solution . . . . . . TWS
  11. Subscribercoquette
    Already mated
    Omaha, Nebraska, USA
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    08 Sep '14 04:05
    Originally posted by lemondrop
    11 is open for a solution
    For 11, I'll ask the "right-brained"question:

    Why not take the already solved 13 and subtract the already solved 2? Trivial, no? Or am I missing something?
  12. Standard memberwolfgang59
    Quiz Master
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    08 Sep '14 06:40
    Originally posted by coquette
    For 11, I'll ask the "right-brained"question:

    Why not take the already solved 13 and subtract the already solved 2? Trivial, no? Or am I missing something?
    You can only use FOUR 4's
  13. Subscribercoquette
    Already mated
    Omaha, Nebraska, USA
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    12 Sep '14 06:32
    Originally posted by wolfgang59
    You can only use [b]FOUR 4's[/b]
    thanks
  14. Aylesbury
    Joined
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    12 Nov '14 08:18
    11 == 44/(sqrt(4) + sqrt(4))
  15. Joined
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    14 Nov '14 21:151 edit
    =(4!-sqrt(4))*sqrt(4)/4
    =-sqrt(4)(log(log(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(sqrt(4))))))))))))/log(4)))/log(4)
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