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A153743
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Number of elements in wreath product C_4\wr S_n that alternate up/not-up with respect to a weak product ordering.
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0
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4, 10, 100, 565, 9356, 79584, 1844492, 20922625, 623457040, 8840131486, 321957866768, 5478133336309, 235789017471008, 4680625831294820, 232457094647793632, 5273696164520751265, 296832635265929103616
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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FORMULA
| E.g.f: (6+6sin(x)+18x*cos(x)-9x^2*sin(x)-x^3*cos(x))/(6cos(x)-18x*sin(x)-9x^2*cos(x)+x^3*sin(x))
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EXAMPLE
| Viewing elements in one-line notation as a list of ordered pairs with first entries in [4] and second entries forming a permutation in S_n, two of the 100 up/not-up elements for n=3 are (1,2) (4,3) (3,1) and (1,1) (1,3) (4,2). Note that the first element goes up/down and the second goes up/not-up with respect to the weak product ordering on ordered pairs.
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CROSSREFS
| Sequence in context: A156329 A203179 A125855 * A197851 A197865 A098449
Adjacent sequences: A153740 A153741 A153742 * A153744 A153745 A153746
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KEYWORD
| nonn
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AUTHOR
| Andy Niedermaier (aniederm(AT)math.ucsd.edu), Dec 31 2008
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