t IS $255
n IS $0
new GREG
old GREG
phii GREG #9e3779b97f4a7c16
lo GREG
hi GREG
hihi GREG
  LOC  #100
Main SET n,2
     SET old,1
     SET new,1
1H   ADDU new,new,old
     INCL n,1
     CMPU t,new,old
     BN   t,9F
     SUBU old,new,old
     MULU lo,old,phii
     GET hi,rH
     ADDU hi,hi,old
     ADDU hihi,hi,1
     CSN hi,lo,hihi
     CMP t,hi,new
     PBZ  t,1B
     SET  t,1
9H   TRAP 0,Halt,0