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 A000083 Number of mixed Husimi trees with n nodes; or polygonal cacti with bridges. (Formerly M1191 N0461) 12
 1, 1, 1, 2, 4, 9, 23, 63, 188, 596, 1979, 6804, 24118, 87379, 322652, 1209808, 4596158, 17657037, 68497898, 268006183, 1056597059, 4193905901, 16748682185, 67258011248, 271452424286, 1100632738565, 4481533246014 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 REFERENCES N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS Christian G. Bower, Table of n, a(n) for n=0..500 G. W. Ford and G. E. Uhlenbeck, Combinatorial problems in the theory of graphs III, Proc. Nat. Acad. Sci. USA, 42 (1956), 529-535. Eric Weisstein's World of Mathematics, Cactus Graph FORMULA G.f.: A(x)=B(x)+C(x)-B(x)*D(x), B, C, D resp gfs of A000237, A035349, A035350. - Christian G. Bower, Nov 15 1998 CROSSREFS Cf. A000237, A000314, A035082, A035349-A035357. Sequence in context: A058585 A001573 A135307 * A092668 A164039 A014137 Adjacent sequences:  A000080 A000081 A000082 * A000084 A000085 A000086 KEYWORD nonn AUTHOR EXTENSIONS More terms from Christian G. Bower, Nov 15 1998 STATUS approved

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