def isAbundantNumber(n): return sumOfProperDivisors(n) > n
# Let d(n) be defined as the sum of proper divisors of n (numbers less than n which divide evenly into n). # If d(a) = b and d(b) = a, where a != b, then a and b are an amicable pair and each of a and b are called amicable numbers. # For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 and 110; therefore d(220) = 284. # The proper divisors of 284 are 1, 2, 4, 71 and 142; so d(284) = 220. # Evaluate the sum of all the amicable numbers under 10000. from common import sumOfProperDivisors total = 0 for a in range(1, 10000): da = sumOfProperDivisors(a) b = da if a != b: db = sumOfProperDivisors(b) if da == b and db == a: total += a print(total)