

A174881


Number of admissible graphs of order n.


2



2, 36, 1728, 160000, 24300000, 5489031744, 1727094849536, 722204136308736, 387420489000000000, 259374246010000000000, 211988959518950443450368, 207728067204059288762843136, 240396446553194784543350546432
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OFFSET

1,1


COMMENTS

In Kontsevich, by definition, an admissible graph of order n is an ordered pair of maps i; j : {1, 2, 3, ..., n} > {1, 2, 3, ..., n, L, R} where neither map has fixed points and both maps are distinct at every point. See p.18 of Dimofte.


REFERENCES

M. Kontsevich, Deformation quantization of Poisson manifolds, Lett. Math. Phys. 66 (2003), no. 3 157{216, [qalg/9709040v1].


LINKS



FORMULA



EXAMPLE

a(1) = (1^1)*((1+1)^1) = 2.
a(2) = (2^2)*((2+1)^2) = 36.
a(3) = (3^3)*((3+1)^3) = 1728.
a(4) = (4^4)*((4+1)^4) = 160000.
a(5) = (5^5)*((5+1)^5) = 24300000.


CROSSREFS



KEYWORD

easy,nonn


AUTHOR



STATUS

approved



