%I #12 Sep 19 2019 19:14:17
%S 1,1,2,4,12,32,89,246,685,1912,5355,15038,42339,119484,337935,957738,
%T 2719539,7736208,22044444,62916696,179841270,514793944,1475586687,
%U 4234989242,12169352003,35009302296,100826681530,290683486132,838873595124
%N a(n) = T(n,n), where T is the array in A026148.
%Y Cf. A026148
%Y First differences of A026325 for n > 1.
%K nonn
%O 0,3
%A _Clark Kimberling_
%E a(0)-a(1) inserted and a(20) corrected by _Sean A. Irvine_, Sep 18 2019