set PR1 = Polynom-Ring (1,R);
set PR = Polynom-Ring R;
set FS1 = Formal-Series (1,R);
set FS = Formal-Series R;
the carrier of (Polynom-Ring (1,R)) c= the carrier of (Formal-Series (1,R)) by Lm7;
then [#] (Polynom-Ring (1,R)) c= dom (BSFSeri R) by FUNCT_2:def 1;
then A1: dom ((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) = [#] (Polynom-Ring (1,R)) by RELAT_1:62;
for o being object st o in the carrier of (Polynom-Ring (1,R)) holds
((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) . o in the carrier of (Polynom-Ring R)
proof
let o be object ; :: thesis: ( o in the carrier of (Polynom-Ring (1,R)) implies ((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) . o in the carrier of (Polynom-Ring R) )
assume A2: o in the carrier of (Polynom-Ring (1,R)) ; :: thesis: ((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) . o in the carrier of (Polynom-Ring R)
then A3: ((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) . o = (BSFSeri R) . o by FUNCT_1:49;
A4: o is finite-Support Series of 1,R by A2, POLYNOM1:def 11;
then A5: o in the carrier of (Formal-Series (1,R)) by Def3;
reconsider f = o as Element of (Formal-Series (1,R)) by A4, Def3;
consider x1 being Series of 1,R such that
A6: ( x1 = o & (BSFSeri R) . o = x1 * NBag1 ) by A5, Def4;
card (Support x1) = card (Support (x1 * NBag1)) by Th44;
then Support (x1 * NBag1) is finite by A4, A6;
then (BSFSeri R) . o is Polynomial of R by A6, Th2;
hence ((BSFSeri R) | ([#] (Polynom-Ring (1,R)))) . o in the carrier of (Polynom-Ring R) by A3, POLYNOM3:def 10; :: thesis: verum
end;
hence (BSFSeri R) | ([#] (Polynom-Ring (1,R))) is Function of (Polynom-Ring (1,R)),(Polynom-Ring R) by A1, FUNCT_2:3; :: thesis: verum