%I A117671
%S A117671 1,6,35,210,1287,8008,50388,319770,2042975,13123110,84672315,548354040,
%T A117671 3562467300,23206929840,151532656696,991493848554,6499270398159,
%U A117671 42671977361650,280576272201225
%N A117671 C(3*n+1,n+1)
%H A117671 Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Two Enumerative 
               Functions</a>
%e A117671 if n=0 then C(3*0+1,0+1)= C(1,1)=1
%e A117671 if n=10 then C(3*10+1,10+1)= C(31,11)=84672315
%Y A117671 Sequence in context: A121838 A001109 A144638 this_sequence A000399 A081051 
               A145145
%Y A117671 Adjacent sequences: A117668 A117669 A117670 this_sequence A117672 A117673 
               A117674
%K A117671 easy,nonn
%O A117671 0,2
%A A117671 Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 12 2006