public static IEnumerable <T> Generate <T>(int count, T a, T b, ICalculate <T> calculate)
{
if (count == 0)
{
yield break;
}
if (count == 1)
{
yield return(a);
}
if (count == 2)
{
yield return(b);
}
for (int i = 0; i < count; i++)
{
var item = b;
b = calculate.CalculateNumber(b, a);
yield return(b);
a = item;
}
}