new; cls;
t1=1; t2=5; dim=3;   /* 3 numbers between t1 and t2 */



N=t2-t1+1-(dim-1);
low=t1+seqa(0,1,dim);
up=low+N-1;
x=low;
print/lz x';                 /* Initial sequence should be included. */
do while not x==up;
   x=recD1index(x,up);
   print/lz x';
endo;

proc recD1index(x,up);
   local dim,j;
   dim=rows(x);
   x[dim]=x[dim]+1;
   j=dim;
   do until j==0;
      if x[j]==up[j]+1;
         x[j-1]=x[j-1]+1;
         if x[j-1]/=up[j-1]+1;
            x[j-1:dim]=x[j-1]+seqa(0,1,dim+1-(j-1));
         endif;
      endif;
      j=j-1;
   endo;
   retp(x);
endp;