/// <summary>
/// Compute multiplier (k)
/// </summary>
private static BigInteger ComputeMultiplier()
{
string one = NetUtility.ToHexString(N.ToByteArray(isUnsigned: true));
string two = NetUtility.ToHexString(g.ToByteArray(isUnsigned: true));
string ccstr = one + two.PadLeft(one.Length, '0');
byte[] cc = NetUtility.FromHexString(ccstr);
using var algorithm = GetHashAlgorithm();
var ccHashed = algorithm.ComputeHash(cc);
Span <char> tmp = stackalloc char[1 + NetUtility.GetHexCharCount(ccHashed.Length)];
tmp[0] = '0'; // ensure that the value is unsigned
NetUtility.ToHexString(ccHashed, tmp[1..]);
