csp dp things

                               {Standal inp, out}
                               {ID Zung Nguyen  }
                               {For the school I've loved}

var c           :       array[0..1000000000] of boolean;

    f           : text;
    u,  max     : longint;
    kt          : byte;


    a, d        : array[0..10000000] of longint; // copy Ngo Huy's words
    N           : longint; //10^7 the length of array A

    {     oh please do not say it's TLE        }

procedure generate;
var i:longint;
begin
     c[1]:=true; u:=1;  kt:=1;  c[0]:=true;
     for i:=1 to 44720 do
     begin
          if i*u>max then break;

          if kt =1 then
          begin
                c[i*u]:=true;
                kt:=2;
          end  else
          begin
                c[i*u+u]:=true;
                kt:=1;
                inc(u);
          end
     end;
end;

procedure reada;
var i:longint;
begin
     readln(n); max:=-10000001;
     for i:=1 to N do
     begin
        read(a[i]);
        if max<a[i] then max:=a[i];
     end;

     if max<=0 then
     begin
          write(0); halt;
     end;
end;

procedure IllfindU;
var i, j, len:longint;
begin


     d[0]:=0; a[0]:=0; len:=0;
     for i:=1 to n do if c[a[i]] then
     begin
          d[i]:=0;
          for j:=0 to i-1 do
          if(a[j]<a[i])and (c[a[j]])and(d[i]<d[j]+1) then  d[i]:=d[j]+1;
          if len<d[i] then len:=d[i];
     end;

     writeln(len);
end;

begin
     reada;
     generate;
     IllfindU;
end.