1program primes(output);
2const n = 50; n1 = 7; (*n1 = sqrt(n)*)
3var i,k,x,inc,lim,square,l: integer;
4    prim: boolean;
5    p,v: array[1..n1] of integer;
6begin
7   write(2:6, 3:6); l := 2;
8   x := 1; inc := 4; lim := 1; square := 9;
9   for i := 3 to n do
10   begin (*find next prime*)
11      repeat x := x + inc; inc := 6-inc;
12         if square <= x then
13            begin lim := lim+1;
14               v[lim] := square; square := sqr(p[lim+1])
15            end ;
16         k := 2; prim := true;
17         while prim and (k<lim) do
18         begin k := k+1;
19            if v[k] < x then v[k] := v[k] + 2*p[k];
20            prim := x <> v[k]
21         end
22      until prim;
23      if i <= n1 then p[i] := x;
24      write(x:6); l := l+1;
25      if l = 10 then
26         begin writeln; l := 0
27         end
28   end ;
29   writeln;
30end .
31