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A321311 Number of linear chord diagrams having n+2 chords and minimal chord length n.

%I A321311 #31 Jan 29 2023 12:42:58
%S A321311 10,26,79,252,796,2468,7564,23012,69676,210308,633484,1905572,5726956,
%T A321311 17201348,51645004,155016932,465214636,1395971588,4188570124,
%U A321311 12567021092,37703684716,113116297028,339359376844,1018099102052,3054339249196,9163101633668,27489472673164
%N A321311 Number of linear chord diagrams having n+2 chords and minimal chord length n.
%H A321311 Andrew Howroyd, <a href="/A321311/b321311.txt">Table of n, a(n) for n = 1..1000</a>
%H A321311 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (5, -6)
%F A321311 a(n) = A293881(n+2,n).
%F A321311 a(n) = 5*a(n-1) - 6*a(n-2) for n > 5.
%F A321311 a(n) = A293156(n) - 5*2^(n-1).
%F A321311 G.f.: x*(10 - 24*x + 9*x^2 + 13*x^3 + 10*x^4)/((1 - 2*x)*(1 - 3*x)). - _Andrew Howroyd_, Nov 17 2018
%F A321311 2*3^4*a(n) = 2^3*73*3^n-5*3^4*2^n for n>3. - _R. J. Mathar_, Jan 25 2023
%t A321311 Join[{10, 26, 79}, LinearRecurrence[{5, -6}, {252, 796}, 24]] (* _Jean-François Alcover_, Nov 24 2018 *)
%o A321311 (PARI) Vec((10 - 24*x + 9*x^2 + 13*x^3 + 10*x^4)/((1 - 2*x)*(1 - 3*x)) + O(x^40)) \\ _Andrew Howroyd_, Nov 17 2018
%Y A321311 A diagonal of A293881.
%Y A321311 Cf. A257113, A293156.
%K A321311 nonn,easy
%O A321311 1,1
%A A321311 _Seiichi Manyama_, Nov 17 2018