import times, strutils, sequtils, math, algorithm, tables, sets, lists, intsets
import critbits, future, strformat, deques
template `max=`(x,y) = x = max(x,y)
template `min=`(x,y) = x = min(x,y)
template `mod=`(x,y) = x = x mod y
template scan2 = (scan(), scan())
template scan3 = (scan(), scan())
let read* = iterator: string {.closure.} =
    while true: (for s in stdin.readLine.split: yield s)
proc scan(): int = read().parseInt
proc scanf(): float = read().parseFloat
proc toInt(c:char): int =
    return int(c) - int('0')




proc dp():seq[float]=
  var d = newseqwith(10^6+1,newseqwith(7,0.0))
  d[0][0]=1.0
  for i in 1..10^6:
    for k in 1..6:
      d[i][k] += d[i-1][k-1]*(7-k).float/6.0 + d[i-1][k]*k.float/6.0
  result = newseq[float]()
  for i in 0..10^6:
    result.add(d[i][6])


var t = dp()

proc solve()=
  echo t[scan()]
  
solve()