Divide factors into Fibonacci and triangular sets
Source: Philippine MO 2023/7
March 19, 2023
number theoryFibonacciPMO
Problem Statement
A set of positive integers is said to be pilak if it can be partitioned into 2 disjoint subsets and , each with at least elements, such that the elements of are consecutive Fibonacci numbers, and the elements of are consecutive triangular numbers. Find all positive integers such that the set containing all the positive divisors of except itself is pilak.