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%I #7 Jul 21 2019 08:17:36
%S 1,1,7,7,7,7,56,105,154,546,1330,2800,7357,17745,47047,116480,290871,
%T 746179,1926638,4908876,12372409,31662582,84227577,217639730,
%U 556964730,1448423004,3868816175,10079702689,26120574753,68425502873,183684723775,482085719682
%N a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=a(2)=1 and a(3)=7.
%K nonn
%O 1,3
%A _Clark Kimberling_