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%I #7 Oct 23 2019 20:34:52
%S 1,2,7,24,77,241,738,2227,6650,19711,58114,170682,499911,1461284,
%T 4265437,12438449,36247956,105589899,307513742,895514715,2607925982,
%U 7595726764,22127052759,64473303788,187912261301,547850119836
%N a(n) = A027113(n, 2n-4).
%K nonn
%O 2,2
%A _Clark Kimberling_