public int ConsecutivePrimeSum(int max)
{
var primes = PrimeNumberHelper.GetPrimeNumbersBelowNumber(max);
var allSums = new List <List <Tuple <int, int> > >();
int i = 0;
while (i < primes.Count)
{
var sums = new List <Tuple <int, int> >();
var next = 0;
var terms = 0;
foreach (var prime in primes.Skip(i))
{
terms++;
next += prime;
if (next > max)
{
allSums.Add(sums);
break;
}
sums.Add(new Tuple <int, int>(terms, next));
}
i++;
}
var combinedSums = allSums.SelectMany(x => x).OrderByDescending(x => x.Item1).ToList();
foreach (var sum in combinedSums)
{
if (primes.Contains(sum.Item2))
{
return(sum.Item2);
}
}
return(-1);
}
public double GetSumOfPrimesBelowNumber(int number)
{
return(PrimeNumberHelper.GetPrimeNumbersBelowNumber(number).Aggregate <int, double>(0, (current, i) => current + i));
}