What is the next mumbers in the series ? 9, 31, 73, 141, _, _, _, ?

Answer 1

9 = 1^2 + 2^3
31 = 2^2 + 3^3
73 = 3^2 + 4^3
141 = 4^2 + 5^3
So
5^2 + 6^3 = 241
6^2 + 7^3 = 379
7^2 + 8^3 = 561