The OEIS is supported by the many generous donors to the OEIS Foundation.
%I #7 Oct 24 2019 19:13:37
%S 5,30,123,472,1790,6794,25879,98952,379674,1461248,5638930,21811540,
%T 84542016,328287506,1276868111,4973645576,19398954626,75753497816,
%U 296142817406,1158865623236,4539024407576,17793358627976,69805770185498
%N a(n) = A027170(2n, n-1).
%K nonn
%O 1,1
%A _Clark Kimberling_