Find the sum of the first 10 terms of the sequence 3+7+13+... (1 Viewer)

bubbletea4lyfe

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Hello can somebody figure out how to :Find the sum of the first 10 terms of the sequence 3+7+13+...
This question is from the Maths In Focus textbook of y12 Mathematics Adv.
The answer is 2146.
Is there a working out for it
 

cossine

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Hello can somebody figure out how to :Find the sum of the first 10 terms of the sequence 3+7+13+...
This question is from the Maths In Focus textbook of y12 Mathematics Adv.
The answer is 2146.
Is there a working out for it
Need more terms.

However, it is clear the series is not arithmetic or geometric.
 

idkkdi

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Hello can somebody figure out how to :Find the sum of the first 10 terms of the sequence 3+7+13+...
This question is from the Maths In Focus textbook of y12 Mathematics Adv.
The answer is 2146.
Is there a working out for it
formula for Tn is (n+1)^2 - n

actually nvm, wrong formula, no way answer is 2146 this way.

another possible formula seems to be every second prime number, but once again that does not work out.
 

CM_Tutor

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Maybe if the question said that the sequence was the sum of an AP and a GP... or better, if its an AP + a GP where ...
 

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