(fofl, size):
floyd: procedure options (main); /* Floyd's Triangle. Wiki 12 July 2012 */

   declare (i, m, n) fixed (10), (j, k, w, nr) fixed binary;

   put list ('How many rows do you want?');
   get list (nr);   /* the number of rows   */
   n = nr*(nr+1)/2; /* the total number of values */

   j,k = 1; m = n - nr + 1;
   do i = 1 to n;
      put edit (i) ( x(1), f(length(trim(m))) );
      if k > 1 then do; k = k - 1; m = m + 1; end;
      else do; k,j = j + 1; m = n - nr + 1; put skip; end;
   end;

end floyd;