SOLUTION: Find the 100th term : 3 , 7 , 17 , 23 , 31.... I have done problems like this before but I cannot seem to find the pattern of these numbers in order to find the 100th term..

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Question 379628: Find the 100th term : 3 , 7 , 17 , 23 , 31....

I have done problems like this before but I cannot seem to find the pattern of these numbers in order to find the 100th term..I appreciate the help.

Found 2 solutions by stanbon, Fombitz:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the 100th term : 3 , 7 , 17 , 23 , 31....
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Linear and Quadratic correlation is not strong.
Cubic correlation is strong (r = 0.9993031...)
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The cubic is f(x) = (1/3)x^3+3.2857x^2-2.3801+2
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Then f(100) = 365954
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Do with that what you wish.
Cheers,
Stan H.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Look at the first differences,
4,10,6,8
Then the second differences,
6,-4,2
The second difference pattern starting with 6 and stepping by alternating signs of 2.
6,-4,2,0,-2,4,-6,8,...
I used an EXCEL spreadsheet.
Then working backwards,
I got the 100th term to be 791.