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A112311 a(1)=1, a(2)=2, a(3)=9; a(n) = n*(n - 2)*a(n - 1)^2/(n - 1). 1
1, 2, 9, 216, 174960, 146932807680, 125937291507579224064000, 108755666689817047890109782510255885778944000000, 93143885917529328515023382841413836868525118214478405334515136630707122998865821696000000000000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Lower bound to number of perfect Morse matchings of n-simplex.

REFERENCES

M. K. Chari and M. Joswig, Complexes of discrete Morse functions, Disc. Math. 302 (2005), 39-51.

CROSSREFS

Cf. A005271.

Sequence in context: A069649 A111832 A114563 * A067564 A165797 A011823

Adjacent sequences:  A112308 A112309 A112310 * A112312 A112313 A112314

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Dec 01 2005

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Last modified February 14 03:34 EST 2012. Contains 205569 sequences.