uses crt;
function Rec(i:integer):longint;
begin
if i=1 then Rec:=1
else Rec:=Rec(i-1)+2;
end;
var n:integer;
begin
clrscr;
write('n=');
readln(n);
write(Rec(n));
readln
end.
uses crt;
function Rec(i:integer):longint;
begin
if i=1 then Rec:=1
else Rec:=Rec(i-1)+2;
end;
var n:integer;
begin
clrscr;
write('n=');
readln(n);
write(Rec(n));
readln
end.