Creating a formula for the sequence 7, 10, 14, 19, 25, 32…

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noobzilla
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Creating a formula for the sequence 7, 10, 14, 19, 25, 32…

Postby noobzilla » Wed Oct 07, 2009 7:14 pm

is the following expression correct? i mean it's logical to me but i'm not sure if you can do this:

tn = tn-1 + 1 + n

Another way of doing it I think could be by looking into quadratics, but i don't want it to be very complicated.

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stapel_eliz
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Postby stapel_eliz » Wed Oct 07, 2009 7:41 pm

The differences are 3, 4, 5, 6, and 7, with t1 = 7 and the differences leading to tn for n > 1. So your formulation looks good. :thumb:

However, if you are supposed to get a closed-form, rather than recursive, formula, you will need to use a quadratic. Use the method explained here. :wink:


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