uses 
   crt; 
var 
   a: array[1..100] of integer; 
   n, i, k: integer; 
begin 
   read(n); 
   k := 0; 
   for i := 1 to n do 
   begin 
     read(a[i]); 
   end; 
   for i := 1 to n do 
   begin 
     if (a[i] <= sqr(i)) then 
       k := k + a[i]; 
   end; 
   write(k); 
   readln; 
   readln; 
end.