BYTE FUNC Gcd(BYTE a,b)
  BYTE tmp

  IF a<b THEN
    tmp=a a=b b=tmp
  FI

  WHILE b#0
  DO
    tmp=a MOD b
    a=b b=tmp
  OD
RETURN (a)

BYTE FUNC Contains(BYTE ARRAY a BYTE len,value)
  BYTE i

  FOR i=0 TO len-1
  DO
    IF a(i)=value THEN
      RETURN (1)
    FI
  OD
RETURN (0)

PROC Generate(BYTE ARRAY seq BYTE count)
  BYTE i,x

  seq(0)=1 seq(1)=2 seq(2)=3
  FOR i=3 TO COUNT-1
  DO
    x=1
    DO
      IF Contains(seq,i,x)=0 AND
        Gcd(x,seq(i-1))=1 AND Gcd(x,seq(i-2))>1 THEN
        EXIT
      FI
      x==+1
    OD
    seq(i)=x
  OD
RETURN

PROC Main()
  DEFINE COUNT="30"
  BYTE ARRAY seq(COUNT)
  BYTE i

  Generate(seq,COUNT)
  PrintF("First %B Yellowstone numbers:%E",COUNT)
  FOR i=0 TO COUNT-1
  DO
    PrintB(seq(i)) Put(32)
  OD
RETURN