MathDB
Functions

Source:

April 28, 2022
function

Problem Statement

Let f(x)f(x) be a function such that f(1)=1234f(1) = 1234, f(2)=1800f(2)=1800, and f(x)=f(x1)+2f(x2)1f(x) = f(x-1) + 2f(x-2)-1 for all integers xx. Evaluate the number of divisors of i=12022f(i)\sum_{i=1}^{2022}f(i)
2022 CCA Math Bonanza Tiebreaker Round #4