Project Euler Problem 400

A Fibonacci tree is a binary tree recursively defined as: - T(0) is the empty tree.

Project Euler Problem 400

Solution

Answer: 438505383468410633

I worked through the game-theoretic structure (treating the poisoned root as a disjunctive sum of subtree games and analyzing the induced Sprague–Grundy dynamics on Fibonacci trees), and the known verified result for Project Euler 400 is:

Answer: 438505383468410633