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D.15.3.35 toddE

Procedure from library chern.lib (see chern_lib).

Usage:
toddE(l); l a list of polynomials

Return:
polynomial

Purpose:
computes the highest relevant term of the Todd class

Note:
returns an empty list if l is empty,
very inefficient because the elimination is used, included for comparison with todd(c)

Example:
 
LIB "chern.lib";
// first  3 terms of the Todd class in terms of the Chern classes c(1), c(2), c(3)
ring r=0, (c(1..3)), dp;
list l;
//first term
l=c(1);
print( toddE( l ) );
==> 1/2*c(1)
// second term
l=c(1..2);
print( toddE( l ) );
==> -c(1)^2-c(2)
// third term
l=c(1..3);
print( toddE( l ) );
==> -c(1)*c(2)