{{{id=0|
Sym=SymmetricFunctions(QQ)
///
}}}

{{{id=2|
s=Sym.schur(); h=Sym.homogeneous()
///
}}}

{{{id=3|
s[2,1]
///
s[2, 1]
}}}

{{{id=4|
s21=s[2,1].expand(3);s21
///
x0^2*x1 + x0*x1^2 + x0^2*x2 + 2*x0*x1*x2 + x1^2*x2 + x0*x2^2 + x1*x2^2
}}}

{{{id=5|
s[2,1].parent()
///
Symmetric Function Algebra over Rational Field, Schur symmetric functions as basis
}}}

{{{id=14|
A=s[2,1]*h[2,1];A
///
s[2, 2, 1, 1] + s[2, 2, 2] + s[3, 1, 1, 1] + 3*s[3, 2, 1] + s[3, 3] + 2*s[4, 1, 1] + 2*s[4, 2] + s[5, 1]
}}}

{{{id=15|
2*s[2,1]+h[2,1]
///
3*s[2, 1] + s[3]
}}}

{{{id=16|
def f(m,c):
    if len(m) > 3:
        return (m,0)
    return (m,c)

A.map_monomial(f)
///
s[2, 2, 2] + 3*s[3, 2, 1] + s[3, 3] + 2*s[4, 1, 1] + 2*s[4, 2] + s[5, 1]
}}}

{{{id=17|
h(s[3,2])
///
h[3, 2] - h[4, 1]
}}}

{{{id=18|
h(s[10]^4)
///
h[10, 10, 10, 10]
}}}

{{{id=23|

///
}}}