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 A091466 Table (by antidiagonals) of labeled alternating octupi with n black nodes and k white nodes. Each type of object labeled from its own label set. 1
 1, 2, 2, 0, 14, 0, 0, 36, 36, 0, 0, 24, 336, 24, 0, 0, 0, 1296, 1296, 0, 0, 0, 0, 2160, 14832, 2160, 0, 0, 0, 0, 1440, 80640, 80640, 1440, 0, 0, 0, 0, 0, 233280, 1082880, 233280, 0, 0, 0, 0, 0, 0, 362880, 7776000, 7776000, 362880, 0, 0, 0, 0, 0, 0, 241920, 33264000 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES F. Bergeron, G. Labelle and P. Leroux, Combinatorial Species and Tree-Like Structures, Cambridge, 1998, p. 113 (2.4.41). LINKS FORMULA Double e.g.f.: A(x, y) = Sum_{i, j>=0} (x^i*y^j/(i!*j!)) = log((1-x*y)^2/(1-x*y*(3+x+y))). EXAMPLE 1  2    0     0       0 ... 2  4   36    24       0 ... 0 36  336  1296    2160 ... 0 24 1296 14832   80640 ... 0  0 2160 80640 1082880 ... CROSSREFS Cf. A029767, A091467. Sequence in context: A117270 A244137 A181389 * A134085 A151339 A228273 Adjacent sequences:  A091463 A091464 A091465 * A091467 A091468 A091469 KEYWORD nonn,tabl AUTHOR Christian G. Bower, Jan 12 2004 STATUS approved

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