Heuristics to highlight

Use numbers, Consider a simpler problem (smaller numbers), Look for patterns.

The base 2 (binary) representation of a positive integer n is the sequence a_ka_k-1a_k-2…a₁a₀, where

n = a_k2^k + a_k-12^k-1 + a_k-22^k-2 + … + a₁2¹ + a₀2⁰,

a_k = 1, and a_i = 0 or 1 for i = 0, 1, …, k-1.

Write down the binary representations of the day today and of the day of the month in which you were born.