public void ShouldReturnInitialTerm()
{
var progression = new ArithmeticSequence(42, 314);
decimal firstTerm = progression.GetSum(1);
firstTerm.Should().Be(42);
}
public object GetResult()
{
const int max = 1000;
const int threesCount = (max - 1) / 3;
const int fivesCount = (max - 1) / 5;
const int fifteensCount = (max - 1) / (3 * 5);
var threes = new ArithmeticSequence(3, 3);
var fives = new ArithmeticSequence(5, 5);
var fifteens = new ArithmeticSequence(15, 15);
return((int)(threes.GetSum(threesCount) + fives.GetSum(fivesCount) - fifteens.GetSum(fifteensCount)));
}