# Enter your code here. Read input from STDIN. Print output to STDOUT

N, n1, n2 =  map(int, input().split())

# dict acting like a dispatcher to calculate series value
l_n = { 3 : lambda x: (x*(x+1))//2 , 5: lambda x: (x*(3*x-1))//2 , 
                    6: lambda x: x*(2*x - 1)  }
    
nc1, nc2 = 1, 1 # two counters to catch up the series without saving value

while True:
    val_n2, val_n1 = l_n[n2](nc2), l_n[n1](nc1)
    ''' compute for the higher order series and let the lower value series catch up '''
    while val_n1 < val_n2:
        nc1 += 1
        val_n1 = l_n[n1](nc1)
    if val_n1 >= N:
        break
    if val_n1 == val_n2:
        print(val_n1)
    nc2 += 1