%I A051133
%S A051133 0,3,30,210,1260,6930,36036,180180,875160,4157010,19399380,89237148,
%T A051133 405623400,1825305300,8143669800,36064823400,158685222960,694247850450,
%U A051133 3022020054900,13095420237900,56517076816200,243023430309660,1041528987041400
%N A051133 C(2n,n)*n*(2n+1)/2.
%F A051133 a(n)=(1/2)*A000984(n+1)*A000217(n). - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               May 05 2007
%F A051133 a(n)=3*A002802(n-1) - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), 
               Jun 02 2007
%p A051133 seq(binomial(2*n,n)*binomial(n,(n-2))/2, n=1..23); - Zerinvary Lajos 
               (zerinvarylajos(AT)yahoo.com), May 05 2007
%p A051133 with(combinat):a:=n->sum(sum(numbcomp(2*n,n)/2, j=2..n),k=1..n): seq(a(n), 
               n=1..23); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 27 
               2007
%Y A051133 Equals 1/2 * A000911(n-1).
%Y A051133 Sequence in context: A003771 A121100 A130546 this_sequence A043030 A120689 
               A136896
%Y A051133 Adjacent sequences: A051130 A051131 A051132 this_sequence A051134 A051135 
               A051136
%K A051133 nonn,easy
%O A051133 0,2
%A A051133 Wouter L. J. Meeussen, wouter.meeussen(AT)pandora.be