const input = ['17'];
const print = this.print || console.log;
const gets = this.gets || ((arr, index) => () => arr[index++])(input, 0);
let n = +gets();
let bearLegs = 2;
let humanLegs = 5;
let chickenLegs = 7;
let count = 0;

for (let bearLegsPair = 0; bearLegsPair <= Math.floor(n / bearLegs); bearLegsPair++) {
    for (let humanLegsPair = 0; humanLegsPair <= Math.floor(n / humanLegs); humanLegsPair++) {
        for (let chickenLegsPair = 0; chickenLegsPair <= Math.floor(n / chickenLegs); chickenLegsPair++) {
            let bear = bearLegs * bearLegsPair;
            let human = humanLegs * humanLegsPair;
            let chicken = chickenLegs * chickenLegsPair;
            let sum = bear + human + chicken;
            if (sum === n) {
                count++;
            }
        }
    }
} print(count);