Program sir;

var f,g:text;
	n,i:byte;
	s,nr:integer;
	st:array[1..256] of integer;

Procedure verif;
var j:integer;suma:integer;
begin
	suma:=0;
	for j:=1 to n do
		suma:=suma+st[j];
	if suma=s then nr:=nr+1;
end;

Procedure bkt(p:byte);
begin
	st[p]:=st[p-1]+1;
	if p=n then verif
	else bkt(p+1);
	st[p]:=st[p-1]-1;
	if p=n then verif
	else bkt(p+1);
end;

begin
	assign(f,'1-sir.in');reset(f);
	assign(g,'1-sir.out'); rewrite(g);
	readln(f,n,s);
	for i:=1 to n do st[i]:=0;
	nr:=0;
	st[1]:=0;
	bkt(2);
	writeln(g,nr);
	close(f);
	close(g);
end.