import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.complex, std.container, std.math, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


struct ModInt(long M) {
  long x;
  this(in ModInt a) { x = a.x; }
  // this(in long a) { x = a % M; if (x < 0) x += M; }
  this(in long a) { x = (a % M + M) % M; }
  ref ModInt opAssign(in long a) { return this = ModInt(a); }
  ref ModInt opOpAssign(string op)(in ModInt a) {
    // static if (op == "+") { x += a.x; if (x >= M) x -= M; }
    // else static if (op == "-") { x -= a.x; if (x < 0) x += M; }
    // else static if (op == "*") { x *= a.x; x %= M; }
    static if (op == "+") { x += a.x; x = (x % M + M) % M; }
    else static if (op == "-") { x -= a.x; x = (x % M + M) % M; }
    else static if (op == "*") { x *= a.x; x = (x % M + M) % M; }
    else static assert(false);
    return this;
  }
  ref ModInt opOpAssign(string op)(in long a) { return mixin("this " ~ op ~ "= ModInt(a)"); }
  ModInt opUnary(string op)() const if (op == "-") { return ModInt(-x); }
  ModInt opBinary(string op, T)(in T a) const { return mixin("ModInt(this) " ~ op ~ "= a"); }
  ModInt opBinaryRight(string op)(in long a) const { return mixin("ModInt(a) " ~ op ~ "= this"); }
  string toString() const { return x.to!string; }
}


enum MO = 10L^^9 + 7;
alias Mint = ModInt!MO;
enum LIM = 10^^6;

long[] inv, fac, invFac;
void prepare() {
  inv = new long[LIM];
  fac = new long[LIM];
  invFac = new long[LIM];
  inv[1] = 1;
  foreach (i; 2 .. LIM) {
    inv[i] = MO - ((MO / i) * inv[cast(size_t)(MO % i)]) % MO;
  }
  fac[0] = invFac[0] = 1;
  foreach (i; 1 .. LIM) {
    fac[i] = (fac[i - 1] * i) % MO;
    invFac[i] = (invFac[i - 1] * inv[i]) % MO;
  }
}
long binom(long n, long k) {
  if (0 <= k && k <= n) {
    assert(n < LIM);
    return fac[cast(size_t)(n)] * invFac[cast(size_t)(k)] % MO * invFac[cast(size_t)(n - k)] % MO;
  } else {
    return 0;
  }
}


Mint solve(long N, long M, long R) {
  debug {
    writefln("N = %s, M = %s, R = %s", N, M, R);
  }
  Mint all = binom(R + N, N);
  debug {
    writeln("  all = ", all);
  }
  Mint sep;
  foreach (x; 1 .. R + 1) {
    if (R - M * x < 0) {
      break;
    }
    Mint sum;
    foreach (t; 0 .. 2) {
      foreach (k; 0 .. N - M + 1) {
        const r = R - M * (x + t) - k * x;
        if (r < 0) {
          break;
        }
        Mint tmp = (k % 2 != 0) ? -1 : +1;
        debug {
          writeln("    ", tmp);
        }
        tmp *= binom(N - M, k);
        tmp *= binom(r + N, N);
        debug {
          writeln("    ", t, " ", k, " ", r, " ", tmp);
          writeln("    sum = ", sum);
        }
        // sum += ((t != 0) ? -1 : +1) * tmp;
        if (t == 0) {
          sum += tmp;
        } else {
          sum -= tmp;
        }
      }
      debug {
        writefln("  x = %s: sum = %s", x, sum);
      }
    }
    sep += sum;
  }
  const ret = all - binom(N, M) * sep;
  debug {
    writeln("  sep = ", sep);
    writeln("  ret = ", ret);
  }
  return ret;
}

void main() {
  prepare();
  
  try {
    for (; ; ) {
      const N = readLong();
      const M = readLong();
      const L = readLong();
      const R = readLong();
      
      const ans = solve(N, M, R) - solve(N, M, L - 1);
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}


Measured memory_bytes: 28156