# <p style="text-align:center"> Errata for Bitcoin and Cryptocurrency Technologies </p> <p style="text-align:center">If you find an error in our book, please email us at <a href="mailto:bitcoinbook@lists.cs.princeton.edu">bitcoinbook@lists.cs.princeton.edu</a>. </p> <p style="text-align:center">This page lists all known substantive errors (typo corrections are also welcome, but not listed here).</p> <p>&nbsp;</p> <table style="height: 397px;"> <tbody> <tr> <td style="width: 10%;"><b>Section</b></td> <td style="width: 10%;"> <p><b>Page (published version)</b></p> </td> <td style="width: 10%;"> <p><b>Page<br/> (free draft version)</b></p> </td> <td style="width: 55%;"><b>Correction</b></td> <td style="width: 10%;"><b>Credit</b></td> </tr> <tr> <td style="width: 10%;">6.2</td> <td style="width: 10%;">&nbsp;143</td> <td style="width: 10%;">170</td> <td style="width: 55%;"> <p><span style="font-weight: 400;">The text states:</span></p> <p><em><span style="font-weight: 400;">Figure 6.1 shows a snippet of the Wikileaks donation page... Notice the refresh button next to the donation address. As you might expect, clicking the&nbsp;</span><span style="font-weight: 400;">button will replace the donation address with an entirely new, freshly generated address. Similarly, if you refresh the page or close it and visit it later, it will have another address, never previously seen. That&rsquo;s because Wikileaks wants to make sure that each donation they receive goes to a new public key that they create just for that purpose. Wikileaks is taking maximal advantage of the ability to create new pseudonyms. This is in fact the best practice for anonymity used by Bitcoin wallets.</span></em></p> <p>The text is correct about the behavior of the refresh button, but wrong about what happens if you refresh the page. Wikileaks and most other <A href="https://en.bitcoin.it/wiki/Donation-accepting_organizations_and_projects">sites that accept cryptocurrency donations</a> use a static address by default for receiving donations, provided they do their own payment processing. Some, like Wikileaks, offer the user the option of requesting a fresh donation address, but most don&rsquo;t. Sites that use a payment processor such as Coinbase or BitPay (instead of doing their own payment processing) benefit from those processors' automatic generation of fresh addresesses.</p> <p>It is unclear why sites don&rsquo;t take advantage of the opportunity for greater privacy. We can think of a few potential reasons: the cognitive benefits of having a single widely-advertised donation address; the engineering complexity of keeping track of an unbounded number of addresses and keys; and publicizing previously received donations as a way to generate social proof.</p> </td> <td style="width: 10%;">Harry Kalodner</td> </tr> <tr> <td style="width: 10%;">&nbsp;8.3</td> <td style="width: 10%;">&nbsp;200</td> <td style="width: 10%;">&nbsp;225</td> <td style="width: 55%;">The text states that it has been proven that there are an infinite number of <a href="https://en.wikipedia.org/wiki/Mersenne_prime">Mersenne primes</a> (primes of the form <em>2<sup>p</sup>-1</em>, where <em>p</em> is prime). This is incorrect, at least as of the time of writing. The statement is a conjecture backed by empirical evidence and widely believed to be true, but like many statements about the distribution of prime numbers, a proof remains elusive.</td> <td style="width: 10%;">Andreas Bender</td> </tr> <tr> <td style="width: 10%;">&nbsp;9.3</td> <td style="width: 10%;">&nbsp;226</td> <td style="width: 10%;">&nbsp;250</td> <td style="width: 55%;"> <span style="font-weight: 400;">In Figure 9.5 (Figure 9.7 in the draft version), the scriptSig for case 1 should be</span> <pre> &lt;BobSignature&gt; &lt;AliceSignature&gt; 1</pre> <p><span style="font-weight: 400;">and for case 2 should be</span></p> <pre> x &lt;AliceSignature&gt; 0</pre> The <tt>1</tt> and <tt>0</tt> were swapped in the text.</td> <td style="width: 10%;">Dimaz Wijaya</td> </tr> <tr> <td style="width: 10%;">&nbsp;9.4</td> <td style="width: 10%;">&nbsp;229</td> <td style="width: 10%;">&nbsp;253</td> <td style="width: 55%;"><span style="font-weight: 400;">The text states that NIST generates their beacon through the output of a quantum mechanical procedure. In fact they generate it using two standard hardware random number generators, although incorporating the output of a Bell violation experiment is a long-term goal.</span></td> <td style="width: 10%;">Rene Peralta, NIST</td> </tr> </tbody> </table>