fcn to_seq(x){ //--> list of ints
   z:=(x.log2()/7);
   (0).pump(z+1,List,'wrap(j){
      x.shiftRight((z-j)*7).bitAnd(0x7f).bitOr((j!=z) and 0x80 or 0)
   });
}

fcn from_seq(in){ in.reduce(fcn(p,n){ p.shiftLeft(7).bitOr(n.bitAnd(0x7f)) },0) }