Brain Teasers
The Never-ending Series
In order to produce the next number in the series, we take the current number, square it, and then add up the digits. This becomes the next term in the sequence.
Starting with 11 as the 1st term, what is the 2008th term in this sequence?
Starting with 11 as the 1st term, what is the 2008th term in this sequence?
Answer
The answer is 13.The first few work out like so:
11, (121) 4, (16) 7, (49) 13, (169) 16, (256) 13....
After the first few, it will jump back and forth between 16 and 13. Seeing how 13 is our 4th term, 16 is our 5th, logic says that 13 will be our 2008th term since it repeats on every even nth term.
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Comments
this my first time and i cant figure out how in the world you would do this....hahaha!!!
It would take the acerage guy anout fufteen minutes to do this correctly with a calculator, IMHO. Good quiz, tough but good...
How many minutes is 'fufteen' minutes? o_o
Nice. Easy if you are good at math. Pretty easy if even you aren't.
cool! Man that was really awesome!
WHAT is after thirteen ???????
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