Abstract: | Let K be either the rational number field Bbb Q{Bbb Q} or an imaginary quadratic field. We give irrationality results for the number q = ?n=1¥rn/(qn-rl)theta=sum_{n=1}^{infty}{r^n}/(q^n-r^l), where q (∣q∣ > 1) is an integer in K, r∈ K × (∣r∣ < ∣q∣), and 1 £ l ? Bbb Z1le lin{Bbb Z} with q n ≠ r l (n ≥ 1). |