public void AsStringWithPrefix()
    {
        var seq = new SpreadLongSequence(0);

        Assert.Equal("C-9E3779B97F4A936D", seq.NextAsString("C-"));
        Assert.Equal("C-3C6EF372FE9526DA", seq.NextAsString("C-"));
        Assert.Equal("C-DAA66D2C7DDFBA47", seq.NextAsString("C-"));
        Assert.Equal("C-78DDE6E5FD2A4DB4", seq.NextAsString("C-"));
        Assert.Equal("C-1715609F7C74E121", seq.NextAsString("C-"));
        Assert.Equal("C-B54CDA58FBBF748E", seq.NextAsString("C-"));
        Assert.Equal("C-538454127B0A07FB", seq.NextAsString("C-"));
        Assert.Equal("C-F1BBCDCBFA549B68", seq.NextAsString("C-"));
        Assert.Equal("C-8FF34785799F2ED5", seq.NextAsString("C-"));
        Assert.Equal("C-2E2AC13EF8E9C242", seq.NextAsString("C-"));
        Assert.Equal("C-CC623AF8783455AF", seq.NextAsString("C-"));
        Assert.Equal("C-6A99B4B1F77EE91C", seq.NextAsString("C-"));
        Assert.Equal("C-08D12E6B76C97C89", seq.NextAsString("C-"));
    }