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D.15.4.31 chWedge

Procedure from library chern.lib (see chern_lib).

Usage:
chWedge(k, r, c [,pos]); k, r integers, c list of polynomials, pos list of integers

Return:
list with entries: int N, list of polynomials l

Purpose:
computes the rank and the Chern classes of the exterior power of a vector bundle

Note:
for the second exterior power chWedge2L(...) could be faster

Example:
 
LIB "chern.lib";
ring r=0, (c(1..5)), dp;
list l=c(1..5);
// the rank and the Chern classes of the second exterior power of a vector bundle of rank 3
print( chWedge(2, 3, l) );
==> [1]:
==>    3
==> [2]:
==>    [1]:
==>       2*c(1)
==>    [2]:
==>       c(1)^2+c(2)
==>    [3]:
==>       c(1)*c(2)-c(3)
// the rank and the first 3 Chern classes
// of the fourth exterior power of a vector bundle of rank 5
print( chWedge(4, 5, l, 1, 2, 3) );
==> [1]:
==>    5
==> [2]:
==>    [1]:
==>       4*c(1)
==>    [2]:
==>       6*c(1)^2+c(2)
==>    [3]:
==>       4*c(1)^3+3*c(1)*c(2)-c(3)