#include <bits/stdc++.h> 
using namespace std;
 
#define repr(i,a,b) for (int i=a; i<b; i++)
#define rep(i,n) for (int i=0; i<  n; i++)
#define PI 3.14159265359  
const long long INF = 1LL << 60;
long long MOD = 1000000007;
long long gcd(long long a, long long b) { return b ? gcd(b, a%b) : a; }
long long lcm (int a, int b){return  (long long) a*b /gcd(a,b);}

int main(){
    int N, K;
    cin >> N >> K;

    vector<int>ab,cd;


    for(int i = 2; i<=2*N ; i++){
        if(i - K >= 2 && i- K <= 2*N){
            ab.push_back(i);
            cd.push_back(i-K);
        }
    }


    long long ans = 0;
    for(int i = 0; i<ab.size(); i++){
        long long x,y;
        if(ab[i] <= N+1) x = ab[i]-1;
        else x = (N+1)*2 - ab[i] -1;

        if(cd[i] <= N+1) y = cd[i]-1;
        else y = (N+1)*2 -cd[i] -1;
        
        ans +=  x * y;
    }

    cout << ans << endl;




}
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<string, string> pss;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<vl> vvl;

double EPS=1e-9;
int INF=1000000005;
long long INFF=1000000000000000005ll;
double PI=acos(-1);
int dirx[8]={ -1, 0, 0, 1, -1, -1, 1, 1 };
int diry[8]={ 0, 1, -1, 0, -1, 1, -1, 1 };
const ll MOD = 1000000007;

ll sum() { return 0; }
template<typename T, typename... Args>
T sum(T a, Args... args) { return a + sum(args...); }

#define DEBUG fprintf(stderr, "====TESTING====\n")
#define VALUE(x) cerr << "The value of " << #x << " is " << x << endl
#define OUT(x) cout << x << endl
#define OUTH(x) cout << x << " "
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define READ(x) for(auto &(z):x) cin >> z;
#define FOR(a, b, c) for (int(a)=(b); (a) < (c); ++(a))
#define FORN(a, b, c) for (int(a)=(b); (a) <= (c); ++(a))
#define FORD(a, b, c) for (int(a)=(b); (a) >= (c); --(a))
#define FORSQ(a, b, c) for (int(a)=(b); (a) * (a) <= (c); ++(a))
#define FORC(a, b, c) for (char(a)=(b); (a) <= (c); ++(a))
#define EACH(a, b) for (auto&(a) : (b))
#define REP(i, n) FOR(i, 0, n)
#define REPN(i, n) FORN(i, 1, n)
#define MAX(a, b) a=max(a, b)
#define MIN(a, b) a=min(a, b)
#define SQR(x) ((ll)(x) * (x))
#define RESET(a, b) memset(a, b, sizeof(a))
#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define ALL(v) v.begin(), v.end()
#define ALLA(arr, sz) arr, arr + sz
#define SIZE(v) (int)v.size()
#define SORT(v) sort(ALL(v))
#define REVERSE(v) reverse(ALL(v))
#define SORTA(arr, sz) sort(ALLA(arr, sz))
#define REVERSEA(arr, sz) reverse(ALLA(arr, sz))
#define PERMUTE next_permutation
#define TC(t) while (t--)
#define FAST_INP  ios_base::sync_with_stdio(false);cin.tie(NULL)
#define what_is(x) cerr << #x << " is " << x << endl;

void solve() {

}

int main()
{
    FAST_INP;
//    #ifndef ONLINE_JUDGE
//    freopen("input.txt","r", stdin);
//    freopen("output.txt","w", stdout);
//    #endif

//    int tc; cin >> tc;
//    TC(tc) solve();
	ll n, k;
	cin >> n >> k;
	k = abs(k);
	ll a, b, c, d, ans = 0;
	FORN(i, 2, 2 * n - k) {
        b = min(n, (ll)i - 1), a = (ll)i - b;
        d = min(n, (ll)i + k - 1), c = (ll)i + k - d;
        ans += (b - a + 1) * (d - c + 1);
    }
	OUT(ans);
    return 0;
}