[9, 99, 999, 9999, ...]

#include <iostream>
#include <stdio.h>
#include <math.h>

using namespace std;

void PlotTable(int n);
double S(int n);

const int n = 5;

int main()
{
    PlotTable(n);
    cout << "S = " << S(n) << endl;

    system("PAUSE");
    return 0;
}

void PlotTable(int n)
{
    cout << "Table = [";
    for (int i = 1; i <= n; i++)
    {
        if (i == n)
        {
            cout << pow(10.0, i) - 1 << "]";
            break;
        }
        cout << pow(10.0, i) - 1 << ", ";
    }
    cout << endl;
}

double S(int n)
{
    if (n == 1) return 9;
    return ( pow(10.0, n) - 1 ) + S(n - 1);
}