$d[1]=1;
@d=(0,
	(        $d[1]  )/6,
	($d[1]*5+$d[2]*2)/6,
	($d[2]*4+$d[3]*3)/6,
	($d[3]*3+$d[4]*4)/6,
	($d[4]*2+$d[5]*5)/6,
	($d[5]  +$d[6]*6)/6
)for 2..<>;
print$d[6]+0