func isAmicable(s *euler.Sieve, a int) bool { if a >= limit { return false } b := s.ProperDivisorSum(a) if b >= limit || a == b { return false } c := s.ProperDivisorSum(b) return a == c }
func isAbundant(s *euler.Sieve, n int) bool { return s.ProperDivisorSum(n) > n }