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#include <bits/stdc++.h>


using namespace std;


const int MOD = 1'000'000'007;


int expo(int a, int n) {
    int ans = 1;

    while (n) {
        if (n & 1LL) {
            ans = ((long long) ans * a) % MOD;
        }

        n >>= 1;
        a = ((long long) a * a) % MOD;
    }

    return ans;
}

int revMod(int a) {
    return expo(a, MOD - 2);
}

void fixNeg(int &x) {
    if (x < 0) {
        x += MOD;
    }
}

void fixBig(int &x) {
    if (x >= MOD) {
        x -= MOD;
    }
}

int getSegmentSum(int l, int r, const vector <int> &pref) {
    int result = pref[r] - (l ? pref[l - 1] : 0);
    fixNeg(result);

    return result;
}

int computeSpecialSum(int x, int y, int n, int diff, int diffPow, int revModDiff) {
    int result = ((long long) n * expo(x, n - 1)) % MOD;
    result = ((long long) result * diff) % MOD;
    result -= diffPow;
    fixNeg(result);

    int revModDiffSquared = ((long long) revModDiff * revModDiff) % MOD;

    return ((long long) result * revModDiffSquared) % MOD;
}

int solve(int n, int k, int m) {
    vector <int> dp1(m, 0), dp2(m, 0), dp1Pref(m, 0), dp2Pref(m, 0), dp1MulPref(m, 0), dp2MulPref(m, 0);
    dp1[0] = dp1Pref[0] = dp2[0] = dp2Pref[0] = 1;

    int kInv = revMod(k);

    for (int x = 1; x < m; x++) {
        dp1[x] = dp1Pref[x - 1];
        dp2[x] = dp2Pref[x - 1];

        if (x >= k + 1) {
            dp1[x] -= dp1Pref[x - k - 1];
            dp2[x] -= dp2Pref[x - k - 1];

            fixNeg(dp1[x]);
            fixNeg(dp2[x]);
        }

        dp1[x] = ((long long) dp1[x] * kInv) % MOD;
        dp1Pref[x] = (dp1[x] + dp1Pref[x - 1]) % MOD;

        dp2[x] = ((long long) dp2[x] * kInv + dp1[x]) % MOD;
        dp2Pref[x] = (dp2[x] + dp2Pref[x - 1]) % MOD;

        dp1MulPref[x] = ((long long) x * dp1[x] + dp1MulPref[x - 1]) % MOD;
        dp2MulPref[x] = ((long long) x * dp2[x] + dp2MulPref[x - 1]) % MOD;
    }

    int numMoves = 0;
    int numTilings = 0;

    for (int cross = max(0, m - k); cross < m; cross++) {
        if (!dp1[cross]) {
            continue;
        }

        int dpDiff = dp2[cross] - dp1[cross];
        fixNeg(dpDiff);

        int rowsShared = 0;
        int movesShared = 0;

        int pos1 = max(0, cross - k + 1);
        int pos2 = m - 1 - k;
        int pos3 = max(pos1, pos2 + 1);
        int pos4 = cross - 1;

        if (pos1 <= pos2) {
            int diff = k - cross;
            fixNeg(diff);

            rowsShared = ((long long) diff * getSegmentSum(pos1, pos2, dp1Pref) + rowsShared) % MOD;
            movesShared = ((long long) diff * getSegmentSum(pos1, pos2, dp2Pref) + movesShared) % MOD;

            rowsShared += getSegmentSum(pos1, pos2, dp1MulPref);
            movesShared += getSegmentSum(pos1, pos2, dp2MulPref);

            fixBig(rowsShared);
            fixBig(movesShared);
        }

        if (pos3 <= pos4) {
            int diff = m - 1 - cross;
            rowsShared = ((long long) diff * getSegmentSum(pos3, pos4, dp1Pref) + rowsShared) % MOD;
            movesShared = ((long long) diff * getSegmentSum(pos3, pos4, dp2Pref) + movesShared) % MOD;
        }

        int diff = m - 1 - cross;
        int rowsBefore = ((long long) diff * dp1[cross] + rowsShared) % MOD;
        int movesBefore = ((long long) diff * dp2[cross] + movesShared) % MOD;

        diff = k - (m - cross) + 1;
        int rowsAt = ((long long) diff * dp1[cross]) % MOD;
        int movesAt = ((long long) diff * dpDiff) % MOD;

        int rowsAfter = ((long long) k * dp1[cross] + rowsShared) % MOD;
        int movesAfter = ((long long) k * dpDiff + movesShared) % MOD;

        int specialDiff = rowsBefore - rowsAfter;
        fixNeg(specialDiff);

        int specialDiffPow = expo(rowsBefore, n) - expo(rowsAfter, n);
        fixNeg(specialDiffPow);

        int revModDiff = revMod(specialDiff);

        int innerSum = ((long long) specialDiffPow * revModDiff) % MOD;
        int innerSumBefore = computeSpecialSum(rowsBefore, rowsAfter, n, specialDiff, specialDiffPow, revModDiff);

        specialDiff *= -1;
        revModDiff *= -1;
        specialDiffPow *= -1;
        fixNeg(specialDiff);
        fixNeg(revModDiff);
        fixNeg(specialDiffPow);

        int innerSumAfter = computeSpecialSum(rowsAfter, rowsBefore, n, specialDiff, specialDiffPow, revModDiff);

        innerSumBefore = ((long long) rowsAt * innerSumBefore) % MOD;
        innerSumAfter = ((long long) rowsAt * innerSumAfter) % MOD;

        numTilings = ((long long) rowsAt * innerSum + numTilings) % MOD;
        numMoves = ((long long) movesBefore * innerSumBefore + numMoves) % MOD;
        numMoves = ((long long) movesAfter * innerSumAfter + numMoves) % MOD;
        numMoves = ((long long) (movesAt + rowsAt) * innerSum + numMoves) % MOD;
    }

    return ((long long) numMoves * revMod(numTilings)) % MOD;
}

int main() {
    ios_base::sync_with_stdio(false);

    int n, k, m;
    cin >> n >> k >> m;

    cout << solve(n, k, m);

    return 0;
}