project_euler.problem_137.sol1 ============================== .. py:module:: project_euler.problem_137.sol1 .. autoapi-nested-parse:: Project Euler Problem 137: https://projecteuler.net/problem=137 Fibonacci Golden Nuggets The polynomial sequence can be rewritten in the finite form: A_F(x) = x / (1 - x - x^2) And then the problem is to solve for it for rational x that give A_F(x) as positive integer. It turns out that the solution is for the n-th golden nugget is given by F(2n) * F(2n + 1), where F(k) is the k'th Fibonacci number. Reference: https://oeis.org/A081018 Functions --------- .. autoapisummary:: project_euler.problem_137.sol1.solution Module Contents --------------- .. py:function:: solution(n: int = 15) -> int It calculates fibonachi numbers 2n and 2n+1, and returns their product. >>> solution(3) 104 >>> solution(10) 74049690