EN
We completely solve the Diophantine equations $x² + 2^{a}{q}^b = yⁿ$ (for q = 17, 29, 41). We also determine all $C = p₁^{a₁} ⋯ p_k^{a_k}$ and $C = 2^{a₀}p₁^{a₁} ⋯ p_k^{a_k}$, where $p₁,...,p_k$ are fixed primes satisfying certain conditions. The corresponding Diophantine equations x² + C = yⁿ may be studied by the method used by Abu Muriefah et al. (2008) and Luca and Togbé (2009).