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%I #7 Oct 24 2019 19:13:55
%S 3,19,76,283,1046,3890,14582,55051,209062,797806,3056868,11752674,
%T 45316896,175175816,678639146,2634146411,10241938406,39882831446,
%U 155519160716,607181138846,2373227900936,9285480209456,36364319046896
%N a(n) = A027170(2n-1, n-1).
%K nonn
%O 1,1
%A _Clark Kimberling_