SOLUTION: what would be the number in the blank space below? 1 8 17 30 _ 76

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Question 983763: what would be the number in the blank space below?
1 8 17 30 _ 76
Answer by solver91311(24713) About Me  (Show Source):
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                  1   8   17    30    __    76

Differences         7   9    13   __     __

Diff of Diff          2    4   

Diff of diff of diff     2   


Presuming the difference of the differences of the differences is constant, and then working back UP the table:

                  1   8   17    30    49    76

Differences         7   9    13   19    27

Diff of Diff          2    4    6    8   

Diff of diff of diff     2   2    2

John

My calculator said it, I believe it, that settles it