Challenge 13: Numerical Recycling
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• Download the handout for Challenge 13.
• Watch the video responses.
• Explore the follow-up challenges.
• Share your ideas in the comments section.

 

Video Responses

Reach out to share your solution and have it included here! :)

 

Follow-up Challenges

• Suppose we change Step 1 of the procedure so that we cube the number (instead of squaring). How would this change the overall behavior of the machine?
  
• Suppose we change Step 2 of the procedure as follows: If the digit-sum has more than one digit, find its digit sum. Continue until the result has just one digit and pass this single digit back to Step 1. For instance, if we get the number 256 in Step 2, we find the digit sum 2+5+6 = 13. The sum has more than one digit and so we do the digit-sum step again: 1 + 3 = 4. We send the result 4 back to Step 1. How would this change the overall behavior of the machine?