Question 168
After expanding the polynomial $(1 + x + y)^{2023}$ and collecting like terms, we obtain the expression
$$
a_0 + a_1x + a_2y + a_3x^2 + a_4xy + a_5y^2 + \dots + a_ky^{2023}
$$
Find the total number of $a_i$'s which are divisible by $5$.
$$
a_0 + a_1x + a_2y + a_3x^2 + a_4xy + a_5y^2 + \dots + a_ky^{2023}
$$
Find the total number of $a_i$'s which are divisible by $5$.