Question

complete series 5,9,17,33,65,129,?

Answer 1

The answer is 257..

The trick is double of the first no. and then subtract 1 from it.

Thanks!!
Hope this helps you :-)

Answer 2

5*2-1=9
9*2-1=17
17*2-1=33
...
...
129*2-1=257
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