Theoretical frequency distribution in echelle diagrams for a representative sdB model. The right-hand side panel shows the echelle diagram for the computed ℓ = 1 modes (red dots) with a period spacing ΔΠ_ℓ = 1 = 266.25 s. The left-hand side panel is the echelle diagram for the computed ℓ = 2 series (blue dots) with ΔΠ_ℓ = 2 = 153.72 s. Deviation from strict asymptotic period relations is caused by structural features inside the sdB star and qualitatively shows similar patterns as observed in Fig. 11.