/////////////////////////////////No.311 z in FizzBuzzString 
    //入力文字読み取り
   //var inputall = require('fs').readFileSync('/dev/stdin', 'utf8');

    //すべて受け取り改行で区切って格納
   var inputnumber = Number(inputall);

    //3の倍数
   var i = 1
   var three = [];
   var threenum=0
   while (true) {
       threenum = i * 3
       if (inputnumber < threenum) {
           break;
       }
       three.push(threenum)
       i++
   }

    //5の倍数
   var i = 1
   var five = [];
   var fivenum = 0
   while (true) {
       fivenum = i * 5
       if (inputnumber < fivenum) {
           break;
       }
       five.push(fivenum)
       i++
   }

    //15の倍数
   var i = 1
   var fifteen = [];
   var fifteennum = 0
   while (true) {
       fifteennum = i * 15
       if (inputnumber < fifteennum) {
           break;
       }
       fifteen.push(fifteennum)
       i++
   }

    var result = (three.length +five.length)*2 

    console.log(result);