%I A008795
%S A008795 1,0,3,1,6,3,10,6,15,10,21,15,28,21,36,28,45,36,55,45,66,
%T A008795 55,78,66,91,78,105,91,120,105,136,120,153,136,171,153,
%U A008795 190,171,210,190,231,210,253,231,276,253,300,276,325,300
%N A008795 Molien series for 3-dimensional group [2,n]+ = 22n.
%C A008795 a(n-3) = number of ordered triples of positive integers which are the 
               side lengths of a nondegenerate triangle of perimeter n. - Rob Pratt 
               (Rob.Pratt(AT)sas.com), Jul 12 2004
%D A008795 Ira Rosenholtz, Problem 1584, Mathematics Magazine, Vol. 72 (1999), p. 
               408.
%H A008795 <a href="Sindx_Mo.html#Molien">Index entries for Molien series</a>
%F A008795 The signed version with g.f. (1-x^3)/(1-x^2)^3 is the inverse binomial 
               transform of A084861. - Paul Barry (pbarry(AT)wit.ie), Jun 12 2003
%F A008795 a(n) = binom(n/2+2, 2) for n even, binom((n+1)/2, 2) for n odd - Rob 
               Pratt (Rob.Pratt(AT)sas.com), Jul 12 2004
%F A008795 a(n-2) interleaves n(n+1)/2 and n(n-1)/2. G.f.: (1-x+x^2)/((1+x)^2(1-x)^3)); 
               a(n)=(2n^2+6n+7)/16+3(2n+3)(-1)^n/16. - Paul Barry (pbarry(AT)wit.ie), 
               Jul 29 2004
%p A008795 (1+x^3)/(1-x^2)^3
%t A008795 Table[If[EvenQ[n], Binomial[n/2+2, 2], Binomial[(n+1)/2, 2]], {n, 0, 
               49}]
%Y A008795 Cf. A005044.
%Y A008795 First differences of A053307.
%Y A008795 Sequence in context: A107884 A158822 A121443 this_sequence A165188 A132180 
               A126191
%Y A008795 Adjacent sequences: A008792 A008793 A008794 this_sequence A008796 A008797 
               A008798
%K A008795 nonn,easy
%O A008795 0,3
%A A008795 N. J. A. Sloane (njas(AT)research.att.com).