fibonacci

The point of the benchmark is to compare the relative speeds of roughly the same Fibonacci code out of the box.

The person you are interviewing may not even know nor want to care what a Fibonacci sequence is.

The generating function for Fibonacci numbers is x/(1-x-x^2) = \sum_{n\geq0} F_n x^n, so you just let x = 1e-24.

By the way, Mathematica's formula looks a lot like the closed form for the Fibonacci sequence.

He came in for the interview, and fumbled through our generic tests (program fibonacci in the language of your choice, etc).

It follows that a_n satisfies the Fibonacci recurrence a_{n+1} = a_n + a_{n-1}.

Yep, point is not to test if they know Fibonacci or prime numbers.

But here is the (sad?) reality: There will always be someone else applying for the same job, who knows what fibonacci numbers are.

I got about two minutes into the fibonacci tutorial before I couldn't stand watching any more.

A common warm up question in a coding interview is to write (on the whiteboard) a program that prints the Fibonacci numbers in sequence.

Hmm, can I get Wolfram Alpha to compute a closed form solution of a recurrent sequence - like the Fibonacci numbers?

> Or write a function that takes an integer and returns that integer's index on the Fibonacci sequence.

(There is a theoretically important data structure called a Fibonacci heap, but I don't believe there is any connection between these and these "Fibonacci trees" other than that in both cases there is something you can count with Fibonacci numbers.) 2.

(with each block being 24 digits long), how would I express that number?" Well, calling the Fibonacci numbers f_n (with f_1=0), that decimal expansion you want is sum (f_n 10^(-24n)) over n≥1.

For dealing with heterogeneous bases, as with measuring in imperial units, take a look at the fraction notation in Fibonacci’s book.

So, why is it such a stretch to ask people to solve Fibonacci?

A few examples (perhaps HelloWord and Fibonacci) in other languages would be nice.