Buggy python submission (verdict: Time Limit Exceeded):
B, W = map(int, input().split())

MOD = 10 ** 9 + 7
M = 200005
fact = [0] * M
fact[0] = 1
for i in range(1, M):
    fact[i] = fact[i - 1] * i
    fact[i] %= MOD

rfact = [0] * M
rfact[M - 1] = pow(fact[M - 1], MOD - 2, MOD)
for i in range(M - 2, -1, -1):
    rfact[i] = rfact[i + 1] * (i + 1)
    rfact[i] %= MOD


def comb(n, k):
    if k < 0 or k > n:
        return 0
    return fact[n] * rfact[n - k] * rfact[k] % MOD


num = [0] * 200005
f = [0] * 200005
for i in range(W):
    q = pow(pow(2, i + B), MOD - 2, MOD) * comb(i + B - 1, B - 1) % MOD
    f[i + B] = q

g = [0] * 200005
for i in range(B):
    q = pow(pow(2, i + W), MOD - 2, MOD) * comb(i + W - 1, W - 1) % MOD
    g[i + W] = q
    num[i + W + 1] = q

pB, pW = 0, 0
for i in range(1, B + W + 1):
    d = 1 - (pB + pW) + 2 * MOD
    d %= MOD
    pB += f[i]
    pB %= MOD
    pW += g[i]
    pW %= MOD

    num[i] += num[i - 1]
    num[i] %= MOD
    print((pow(2, MOD - 2, MOD) * d + num[i]) % MOD)


Fixed submission:
B, W = map(int, input().split())

MOD = 10 ** 9 + 7
M = 200005
fact = [0] * M
fact[0] = 1
for i in range(1, M):
    fact[i] = fact[i - 1] * i
    fact[i] %= MOD

rfact = [0] * M
rfact[M - 1] = pow(fact[M - 1], MOD - 2, MOD)
for i in range(M - 2, -1, -1):
    rfact[i] = rfact[i + 1] * (i + 1)
    rfact[i] %= MOD

pow2 = [0] * M
pow2[0] = 1
for i in range(1, M):
    pow2[i] = pow2[i - 1] * 2
    pow2[i] %= MOD


def comb(n, k):
    if k < 0 or k > n:
        return 0
    return fact[n] * rfact[n - k] * rfact[k] % MOD


num = [0] * 200005
f = [0] * 200005
for i in range(W):
    q = pow(pow2[i + B], MOD - 2, MOD) * comb(i + B - 1, B - 1) % MOD
    f[i + B] = q

g = [0] * 200005
for i in range(B):
    q = pow(pow2[i + W], MOD - 2, MOD) * comb(i + W - 1, W - 1) % MOD
    g[i + W] = q
    num[i + W + 1] = q


inv2 = pow(2, MOD - 2, MOD)
pB, pW = 0, 0
for i in range(1, B + W + 1):
    d = 1 - (pB + pW) + 2 * MOD
    d %= MOD
    pB += f[i]
    pB %= MOD
    pW += g[i]
    pW %= MOD

    num[i] += num[i - 1]
    num[i] %= MOD
    print((inv2 * d + num[i]) % MOD)

Buggy python submission (verdict: Runtime Error):
B, W = map(int, input().split())

MOD = 10 ** 9 + 7
M = 100005
fact = [0] * M
fact[0] = 1
for i in range(1, M):
    fact[i] = fact[i - 1] * i
    fact[i] %= MOD

rfact = [0] * M
rfact[M - 1] = pow(fact[M - 1], MOD - 2, MOD)
for i in range(M - 2, -1, -1):
    rfact[i] = rfact[i + 1] * (i + 1)
    rfact[i] %= MOD


def comb(n, k):
    if k < 0 or k > n:
        return 0
    return fact[n] * rfact[n - k] * rfact[k] % MOD


num = [0] * 200005
f = [0] * 200005
for i in range(W):
    q = pow(pow(2, i + B), MOD - 2, MOD) * comb(i + B - 1, B - 1) % MOD
    f[i + B] = q

g = [0] * 200005
for i in range(B):
    q = pow(pow(2, i + W), MOD - 2, MOD) * comb(i + W - 1, W - 1) % MOD
    g[i + W] = q
    num[i + W + 1] = q

pB, pW = 0, 0
for i in range(1, B + W + 1):
    d = 1 - (pB + pW) + 2 * MOD
    d %= MOD
    pB += f[i]
    pB %= MOD
    pW += g[i]
    pW %= MOD

    num[i] += num[i - 1]
    num[i] %= MOD
    print((pow(2, MOD - 2, MOD) * d + num[i]) % MOD)


Fixed submission:
B, W = map(int, input().split())

MOD = 10 ** 9 + 7
M = 200005
fact = [0] * M
fact[0] = 1
for i in range(1, M):
    fact[i] = fact[i - 1] * i
    fact[i] %= MOD

rfact = [0] * M
rfact[M - 1] = pow(fact[M - 1], MOD - 2, MOD)
for i in range(M - 2, -1, -1):
    rfact[i] = rfact[i + 1] * (i + 1)
    rfact[i] %= MOD

pow2 = [0] * M
pow2[0] = 1
for i in range(1, M):
    pow2[i] = pow2[i - 1] * 2
    pow2[i] %= MOD


def comb(n, k):
    if k < 0 or k > n:
        return 0
    return fact[n] * rfact[n - k] * rfact[k] % MOD


num = [0] * 200005
f = [0] * 200005
for i in range(W):
    q = pow(pow2[i + B], MOD - 2, MOD) * comb(i + B - 1, B - 1) % MOD
    f[i + B] = q

g = [0] * 200005
for i in range(B):
    q = pow(pow2[i + W], MOD - 2, MOD) * comb(i + W - 1, W - 1) % MOD
    g[i + W] = q
    num[i + W + 1] = q


inv2 = pow(2, MOD - 2, MOD)
pB, pW = 0, 0
for i in range(1, B + W + 1):
    d = 1 - (pB + pW) + 2 * MOD
    d %= MOD
    pB += f[i]
    pB %= MOD
    pW += g[i]
    pW %= MOD

    num[i] += num[i - 1]
    num[i] %= MOD
    print((inv2 * d + num[i]) % MOD)