public static List <Tuple <int, int> > GetPrimeFactors(this long number)
{
List <Tuple <int, int> > returnFactorisation = new List <Tuple <int, int> >();
foreach (int currentPrime in Sequences.CachedPrimes().TakeWhile(p => p <= number))
{
int timesDivisible = 0;
while (number % currentPrime == 0)
{
timesDivisible++;
number = number / currentPrime;
}
if (timesDivisible > 0)
{
returnFactorisation.Add(Tuple.Create(currentPrime, timesDivisible));
}
}
return(returnFactorisation);
}
public static List <KeyValuePair <int, int> > PrimeFactors(int value)
{
var primeFactors = new List <KeyValuePair <int, int> >();
foreach (var p in Sequences.PrimesUpTo(1, value))
{
var pair = new KeyValuePair <int, int>(p, 0);
while (value % p == 0)
{
pair = new KeyValuePair <int, int>(p, pair.Value + 1);
value = value / p;
}
if (pair.Value > 0)
{
primeFactors.Add(pair);
}
}
return(primeFactors);
}