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Everything posted by rocdocmac

  1. Cubicle Stack

    Thank you Bonanova for your input! To all participants ... The 3-cubelet removal question has now been submitted as a separate new entry called "Cubicle Stack #2" since the thread sort of "got lost" in the original Cubicle Stack discussion after having been solved!
  2. A simple integration paradox?

    ∫1/(2x) = ½ln|x| + c. ln|2x| = ln|x| + ln(2), where ln(2) is a constant
  3. Whodunit?

  4. Whodunit?

  5. Whodunit?

    My final answer:
  6. Whodunit?

  7. Whodunit?

  8. Cubicle Stack

    Does anyone want to attempt figuring out the number of patterns if three of the cubelets are omitted rather than one or two?
  9. Largest unit sphere

  10. What is the sum of the unit volumes of n-dimensional spheres for the infinite series 1, 2r, πr² , ⁴/₃ πr3, ...
  11. Cubicle Stack

  12. Cubicle Stack

  13. Cubicle Stack

  14. Cubicle Stack

  15. Cubicle Stack

  16. Cubicle Stack

    My question and image seem to have disappeared! Suppose 27 identical cubes are glued together to form a cubical stack, as illustrated below. If one of the small cubes is omitted, four distinct shapes are possible: one in which the omitted cube is at a corner of the stack, one in which it is in the middle of an edge of the stack, one in which it is in the middle of a side of the stack, and one in which it is at the core of the stack. If two of the small cubes are omitted rather than just one, how many distinct shapes are possible?
  17. What is the missing number?

    Reason for giving 12:
  18. How many squares?

    Thanks for the Christmas tree idea! Changed the red to green. Hope my sketch is close enough! Don't know how to put an image into the spoiler section only - Sorry for that glitch.