public void AtRfcExamples()
{
Totp totp = createTotp("GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ");
Assert.AreEqual("050471", totp.At(1111111111));
Assert.AreEqual("005924", totp.At(1234567890));
Assert.AreEqual("279037", totp.At(2000000000));
}