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%I #17 Dec 25 2023 10:00:12
%S 0,3,4,19,32,79,127,283,459,940,1520,2982,4826,9171,14838,27581,44628,
%T 81557,131961,237995,385085,687158,1111844,1966764,3182292,5588259,
%U 9041992,15780103,25532744,44323195,71716435,123920827,200508111,345062176,558322328,957403026
%N a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n-k+1), where k = [n/2], s = (Lucas numbers).
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (1,3,-2,0,-2,-3,1,1).
%F From _Chai Wah Wu_, Dec 24 2023: (Start)
%F a(n) = a(n-1) + 3*a(n-2) - 2*a(n-3) - 2*a(n-5) - 3*a(n-6) + a(n-7) + a(n-8) for n > 8.
%F G.f.: x*(-4*x^5 - 2*x^4 + 7*x^3 + 6*x^2 + x + 3)/((x^2 + 1)*(-x^2 + x + 1)*(x^2 + x - 1)^2).
%F (End)
%t a[n_]:=Sum[LucasL[i]LucasL[n-i+1],{i,Floor[n/2]}]; Array[a,36] (* _Stefano Spezia_, Dec 24 2023 *)
%Y Cf. A000204 (Lucas), A004526 ([n/2]).
%K nonn,easy
%O 1,2
%A _Clark Kimberling_
%E a(1) inserted by _Chai Wah Wu_, Dec 24 2023
%E More terms from _Stefano Spezia_, Dec 24 2023
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