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%I A357596 #10 Oct 08 2022 14:17:03
%S A357596 1,1,3,15,105,923,9417,105815,1267681,15875631,205301361
%N A357596 Number of marked chord diagrams (linear words in which each letter appears twice) with n chords, whose intersection graph is distance-hereditary.
%C A357596 For n < 5, all intersection graphs on n vertices are distance-hereditary, so the first 4 terms coincide with the number of linear chord diagrams (given by the double factorial numbers; see A001147).
%H A357596 Christopher-Lloyd Simon, <a href="https://arxiv.org/abs/2106.15450">Topologie et dénombrement des courbes algébriques réelles</a>, arXiv:2106.15450 [math.AG], 2021.
%H A357596 Christopher-Lloyd Simon, <a href="https://doi.org/10.5802/afst.1698">Topologie et dénombrement des courbes algébriques réelles</a>, Annales de la faculté des sciences de Toulouse : Mathématiques, 6e série, 31(2): 383--422, 2022.
%F A357596 G.f. is algebraic: (z^3 + z^2)*A^6 - z^2*A^5 - 4*z*A^4 + (8*z + 2)*A^3 - (4*z + 6)*A^2 + 6*A - 2 = 0.
%Y A357596 Cf. A277862, A277869, A354588.
%K A357596 nonn,more
%O A357596 0,3
%A A357596 _Christopher-Lloyd Simon_, Oct 05 2022

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