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%I #9 May 26 2020 11:00:30
%S 0,3,42,390,2940,19530,119196,684684,3758040,19909890,102539580,
%T 516023508,2547314952,12371513700,59252218200,280374917400,
%U 1312759571760,6089545431090,28014942671100,127932182324100
%N (n+n^2+n^3)*(binomial(2*n,n))/2.
%p [seq ((n+n^2+n^3)*(binomial(2*n,n))/2,n=0..29)];
%t Table[(n+n^2+n^3) Binomial[2n,n]/2,{n,0,20}] (* _Harvey P. Dale_, May 26 2020 *)
%Y Cf. A000984, A027444.
%K easy,nonn
%O 0,2
%A _Zerinvary Lajos_, May 31 2006