theorem Th66:
  mlt(i|->a,R) = a*R & mlt(R,i|->a) = a*R
proof
  thus mlt(i|->a,R) = (the multF of K)[;](a,R) by FINSEQOP:20
    .= a*R by FINSEQOP:22;
  hence thesis by FINSEQOP:33;
end;
