A Recursive Sum

Sequences { a n } n W \{a_n\}_{n \in \mathbb{W}} and { b n } n W \{b_n\}_{n \in \mathbb{W}} are defined as follows:

a 0 = 1 2 a_0 = \frac{1}{2} b 0 = 1 3 b_0 = \frac{1}{3} a n = a 0 a n 1 b 0 b n 1 ( n N ) a_{n} = a_0a_{n-1} - b_0b_{n-1} \hspace{5 mm} (\forall n \in \mathbb{N}) b n = a 0 b n 1 + b 0 a n 1 ( n N ) b_{n} = a_0b_{n-1} + b_0a_{n-1} \hspace{5 mm} (\forall n \in \mathbb{N})

A = n = 0 a n A = \sum_{n=0}^{\infty} a_n B = n = 0 b n B = \sum_{n=0}^{\infty} b_n

If A B \frac{A}{B} can be expressed as p q \frac{p}{q} where p p and q q are coprime natural numbers, enter the value of p + q p+q .


The answer is 17.

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Aryaman Maithani
Apr 19, 2018

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...