genera(CoherentSheaf) -- list of the successive linear sectional arithmetic genera

Synopsis

• Function: genera

• Usage:

  genera M

• Inputs:
  • M, a coherent sheaf
• Outputs:
  • a list, of the successive linear sectional arithmetic genera of the successive generic hyperplane restrictions of M

Description

i1 : V = Proj(ZZ/101[x_0..x_2]);

i2 : M = sheaf(image matrix {{x_0^3+x_1^3+x_2^3}})

o2 = image | x_0^3+x_1^3+x_2^3 |

                                         1
o2 : coherent sheaf on V, subsheaf of OO
                                        V

i3 : genera M

o3 = {0, 3, 0}

o3 : List

See also

• euler -- Euler characteristic