{
TASK:rtri
LANG:PASCAL
}

var
  a: array[1..30,1..30] of Longint;
  n,m: Integer;
  i,j: Integer;

procedure swap;
var
  pom: Integer;

begin
  pom:= n;
  n:= m;
  m:= pom;
end;


begin
  readln(n,m);
  n:= n+1; m:= m+1;
  a[1,1]:= 4;
  for i:= 1 to n do
    for j:= 2 to m do
    begin
      a[i,j]:= (a[i,j-1] + a[i-1,j]) + (i-1)*(j-1) +(j-2)*(i-2);
      a[j,i]:= a[i,j]; 
   end;
   writeln(a[n,m]);
end.