%I A000237 M2754 N1107
%S A000237 0,1,1,3,8,26,84,297,1066,3976,15093,58426,229189,910127,3649165,
%T A000237 14756491,60103220,246357081,1015406251,4205873378,17497745509,
%U A000237 73084575666,306352303774,1288328048865,5433980577776,22982025183983
%N A000237 Number of mixed Husimi trees with n nodes; or rooted polygonal cacti
with bridges.
%D A000237 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences,
Academic Press, 1995 (includes this sequence).
%D A000237 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973
(includes this sequence).
%D A000237 G. W. Ford and G. E. Uhlenbeck, Combinatorial problems in the theory
of graphs III, Proc. Nat. Acad. Sci. USA, 42 (1956), 529-535.
%H A000237 Christian G. Bower, <a href="b000237.txt">Table of n, a(n) for n=0..500</
a>
%H A000237 C. G. Bower, <a href="transforms2.html">Transforms (2)</a>
%H A000237 N. J. A. Sloane, <a href="transforms.txt">Transforms</a>
%H A000237 <a href="Sindx_Ca.html#cacti">Index entries for sequences related to
cacti</a>
%H A000237 <a href="Sindx_Ro.html#rooted">Index entries for sequences related to
rooted trees</a>
%H A000237 <a href="Sindx_Tra.html#trees">Index entries for sequences related to
trees</a>
%F A000237 Shifts left under transform T where Ta = EULER(BIK(a)). [See Transforms
links.]
%Y A000237 Cf. A000083, A000314, A035082, A035349-A035357.
%Y A000237 Sequence in context: A148803 A148804 A148805 this_sequence A148806 A148807
A148808
%Y A000237 Adjacent sequences: A000234 A000235 A000236 this_sequence A000238 A000239
A000240
%K A000237 nonn,eigen,nice,easy
%O A000237 0,4
%A A000237 N. J. A. Sloane (njas(AT)research.att.com).
%E A000237 More terms and formula from Christian G. Bower (bowerc(AT)usa.net), Nov
15 1998
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