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Posers and Puzzles

Posers and Puzzles

  1. Donation Acolyte
    Now With Added BA
    01 Jun '04 21:22
    This game works as follows: by some mathematical rule, I will assign 'odd' or 'even' to all elements of a set. Two elements combined in some way will give even if they are of the same type, and odd if they are not. The object is to guess the rule, by asking whether specific elements are odd or even.

    The first set is the natural numbers (ie 1,2,3,4,5,6....)

    24 is ODD
    100 is EVEN
  2. Standard member royalchicken
    CHAOS GHOST!!!
    01 Jun '04 23:06
    Originally posted by Acolyte
    This game works as follows: by some mathematical rule, I will assign 'odd' or 'even' to all elements of a set. Two elements combined in some way will give even if they are of the same type, and odd if they are not. The object is to guess the rule, by asking whether specific elements are odd or even.

    The first set is the natural numbers (ie 1,2,3,4,5,6....)

    24 is ODD
    100 is EVEN
    Is 64 odd or even?
  3. Donation Acolyte
    Now With Added BA
    02 Jun '04 08:54
    Originally posted by royalchicken
    Is 64 odd or even?
    even
  4. 02 Jun '04 12:09
    How about 32?
  5. Standard member TheMaster37
    Kupikupopo!
    02 Jun '04 12:48
    I would like to know the parity of the following numbers;

    2, 4, 5, 10 and 15. I already have an idea what the rule might be, i'm hoping for EEOOE
  6. Donation Acolyte
    Now With Added BA
    02 Jun '04 16:18 / 1 edit
    2 is ODD
    4 is EVEN
    5 is EVEN
    10 is ODD
    15 is EVEN
    32 is ODD

    Master37: If your rule is what I think it is, you're on the right track; it may in fact only be one word out.

    How's that for a confusing clue?
  7. Standard member TheMaster37
    Kupikupopo!
    02 Jun '04 18:25
    Hmmz....the 5 being even disrupts all my theories...how about 7, 11 and 12?
  8. Donation Acolyte
    Now With Added BA
    02 Jun '04 19:49
    7 is EVEN
    11 is EVEN
    12 is EVEN
  9. 03 Jun '04 13:02
    I need building blocks..

    How about 1,3,8 and 81?
  10. Donation Acolyte
    Now With Added BA
    03 Jun '04 14:00
    1 is EVEN
    3 is EVEN
    8 is ODD
    81 is EVEN
  11. 03 Jun '04 14:32
    I can see this bugging me! Okay, so so far we have

    Even :
    1 3 4 5 7 11 12 15 64 81 and 100.

    Odd :
    2 8 10 24 32

    All of the "odd" numbers are even and all square numbers suggested so far are "even".

    2x32=64 is also the product of two "odd" numbers which gives an "even" result. Hmmm....

    And square numbers are the products of two numbers of the same type.. I'm feeling good about this one!

    Let's test...

    6 and 56, are they both odd?
  12. 03 Jun '04 14:34
    For completeness sake, how about 9 and 6?
  13. 03 Jun '04 14:41
    is 11235840 odd?
  14. Donation Acolyte
    Now With Added BA
    03 Jun '04 18:59
    6 is ODD
    9 is EVEN
    56 is ODD
    11235840 is ODD

    Sound's like you're on to something, mikenay. iamatiger, I'd be intrigued to see the significance of your number.
  15. 03 Jun '04 23:54
    Is the rule this: how many times can n be divided by 2 before a fractional result is produced?

    Put another way, what is the power of 2 in the (unique) factorization of n.

    e.g. 56 = 2^3 x 7 - the power of 2 is odd
    100 = 2^2 x 5^2 - power of 2 is even
    11235840 = 2^9 x 3 x 5 x 7 x 11 x 19 - power of 2 is odd