n,a,b,k = map(int,input().split())
mod = 10**9+7

def calc(x,y):
    ans = [[0]*2 for i in range(2)]
    for i in range(2):
        for j in range(2):
            for k in range(2):
                ans[i][j] += x[i][k]*y[k][j]
                ans[i][j] %= mod
    return ans
base = [[0]*2 for i in range(2)]
for i in range(2):
    base[i][i] = 1

A = [[(a**2+b**2+k)*pow(a*b,mod-2,mod)%mod,-1],[1,0]]
if n == 1:
    print(a)
elif n == 2:
    print(b)
else:
    n -= 2
    while n:
        if n%2:
            base = calc(base,A)
        A = calc(A,A)
        n //= 2
    ans = base[0][0]*b+base[0][1]*a
    print(ans%mod)