A007888 - OEIS

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A007888

Euler characteristic of mapping class group Gamma_n.

1, 1, 3, 2, 3, 4, 1, -6, 45, -86, 173, -100, 2641, -48311, 717766, -15527527, 395694683, -11210796201, 356923346235, -12694851400717, 501010779605741, -21827969798073020, 1044997258445975691, -54740156237911040100

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OFFSET

1,3

REFERENCES

Harer, J., The cohomology of the moduli space of curves, Lecture Notes in Math., Vol. 1337, Springer-Verlag, NY, pp. 138-221

LINKS

Sean A. Irvine, Table of n, a(n) for n = 1..37

CROSSREFS

Sequence in context: A239959 A214435 A215926 * A188723 A341890 A077178

Adjacent sequences: A007885 A007886 A007887 * A007889 A007890 A007891

KEYWORD

sign

AUTHOR

Mira Bernstein

EXTENSIONS

More terms from Sean A. Irvine, Feb 14 2018

STATUS

approved