N = int(input())
C,V = list(map(int, input().split(' ')))

def factorize(n):
    i = 2
    nn = n
    factors = {}
    while i * i <= n:
        if nn % i == 0:
            nn /= i
            if i in factors:
                factors[i] = factors[i] + 1
            else:
                factors[i] = 1
        else:
            i = i + 1
                
    if nn != 1:
        nn = int(nn)
        if nn in factors:
            factors[nn] = factors[nn] + 1
        else:
            factors[nn] = 1
            
    return factors
            
def find(n):
    factors = factorize(n)
    
    minimum = float('inf')
    for factor in factors:
        cost = 0
        rest = C + V * ((n // (factor ** factors[factor]))-1)
        if factor % 2 == 1:
            cost = C + V * (factor-1) + rest
        else:
            cost = (C + V) * factors[factor] + rest
        minimum = min(minimum, cost)

    return min(minimum, C + V * (N-1))

minimum = float('inf')
minimum = min(minimum, find(N))
minimum = min(minimum, find(N+1))
minimum = min(minimum, find(N+2))

print(minimum)