(adsbygoogle = window.adsbygoogle || []).push({}); How to solve recurrence relation with one real root and two complex roots ???

The Example is ;

Solve the recurrence relation a n-1 + a n-3 = 0 where n ≥ 3 and a 1 = 1 a 2 = 1 a 3 = 2

a n = nth order

a n-1 = (n-1)th order.

a n-3 = (n-3)th order.

I've started the solving ;

a n = r^n

so

the equation will be ;

r^n - r^(n-1) - r^(n-3)

r^3 - r^2 - 1 = 0

I could'nt do anything after find the roots ?

What should i do ?

Thanks for helping.

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# How to solve recurrence relation with one real root and two complex roots ?

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