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

Offset: 1

Author

Mira Bernstein

Keywords

• sign

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

Extensions

More terms from Sean A. Irvine, Feb 14 2018