# genus(CoherentSheaf) -- arithmetic genus

## Description

Computes the arithmetic genus of the coherent sheaf F that is (-1)^dim-support * (chi(F) - 1)). If F is a module over a ring, then the genus of F~ is computed. If I is an ideal in a ring R then the genus of (R/I)~ is computed.
 i1 : V = Proj(QQ[x,y,z]/ideal(y^2*z-x^2*(x+z))) o1 = V o1 : ProjectiveVariety i2 : genus OO_V^1 o2 = 1