
function main(input) {
    var N= Number(input.trim());
    var count = 0 
    for (var C = 1; C <N ; C++){
        var X = N-C;
        count = count + Count(X)
    }
    console.log(count);
}


function Count(X){
    var result = 1;
    var array = pf(X);
    for ( var k in array){
        if (k !== "1") result = result * (array[k]+1)
    }
    return result;
}

function pf(n) {
    var result = {};
    
    if (n === 1) {
        return {"1":1}
    }

    var init = 2;

    while (n !== 1) {
        var i = init;
        while (i < Number.MAX_SAFE_INTEGER) {
            if (n % i === 0) {
                n /= i;
                if (!(result[i] > 0)) {
                    result[i] = 0;
                }
                result[i]++;
                break;
            }
            i++;
        }
        init = i;
    }
    return result;
}


main(require('fs').readFileSync('/dev/stdin', 'utf8'));