%I A053507
%S A053507 0,0,1,12,150,2160,36015,688128,14880348,360000000,9646149645,283787919360,
%T A053507 9098660462034,315866083233792,11806916748046875,472877960873902080,
%U A053507 20205339187128111480,917543123840934346752,44131536275846038655193
%N A053507 Binomial(n-1,2)*n^(n-3).
%C A053507 Number of connected unicyclic simple graphs on n labeled nodes such that 
               the unique cycle has length 3. - Len Smiley (smiley(AT)math.uaa.alaska.edu), 
               Nov 27 2001
%C A053507 Each simple graph (of this type) corresponds to exactly two 'functional 
               digraphs' counted by A065513.
%D A053507 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see 
               Prop. 5.3.2.
%F A053507 E.g.f.: -1/3!*LambertW(-x)^3. - Vladeta Jovovic (vladeta(AT)eunet.rs), 
               Apr 07 2001
%Y A053507 Cf. A000169, A053506-A053509, A081133, A081132. Equals 2*A065513. A diagonal 
               of A081130.
%Y A053507 Sequence in context: A056351 A056345 A068768 this_sequence A060917 A113358 
               A015611
%Y A053507 Adjacent sequences: A053504 A053505 A053506 this_sequence A053508 A053509 
               A053510
%K A053507 nonn
%O A053507 1,4
%A A053507 N. J. A. Sloane (njas(AT)research.att.com), Jan 15 2000