The pattern of the series follows two parts: - The first letters: A, D, G, J, ....
are increasing by 3 positions in the alphabet each time.
From J, the next letter is M.
- The numbers: 2, 8, 14, 20, ....
are increasing by 6 each time.
From 20, the next number is 26.
Thus, the next term in the series is M26.
Find $P_1 + P_2 + \dots + P_{10}$ if $P_k$ is the perimeter of a square having side length $k$.