The Common Progression Problem
Algebra
Level
3
I have 2 arithmetic progressions:
\[ \begin{cases}
16,21,26,31, \ldots \\ 21,25,29,33, \ldots \end{cases} \]
The number 21 appears in both of these progressions.
There are also other numbers that appear in both of these 2 progressions!
What is the sum of the first 100 common terms of these 2 progressions?
by
Saswata Naha