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<!-- Describe the issue -->
curl -v http://127.0.0.1:8332/rest/blockhashbyheight/23.json
* About to connect() to 127.0.0.1 port 8332 (#0)
* Trying 127.0.0.1...
* Connected to 127.0.0.1 (127.0.0.1) port 8332 (#0)
> GET /rest/blockhashbyheight/23.json HTTP/1.1
> User-Agent: curl/7.29.0
> Host: 127.0.0.1:8332
> Accept: */*
>
< HTTP/1.1 404 Not Found
< Date: Wed, 30 Jan 2019 03:24:33 GMT
< Content-Length: 0
< Content-Type: text/html; charset=ISO-8859-1
<
* Connection [#0](/bitcoin-bitcoin/0/) to host 127.0.0.1 left intact
<!--- What behavior did you expect? -->
I want to get a json object containing the hexadecimal block hash 000000000cd339982e556dfffa9de94744a4135c53eeef15b7bcc9bdeb9c2182
<!--- What was the actual behavior (provide screenshots if the issue is GUI-related)? -->
<!--- How reliably can you reproduce the issue, what are the steps to do so? -->
<!-- What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)? -->
<!-- What type of machine are you observing the error on (OS/CPU and disk type)? -->
<!-- For the GUI-related issue on Linux provide names and versions of a distro, a desktop environment and a graphical shell (if relevant). -->
<!-- Any extra information that might be useful in the debugging process. -->
<!--- This is normally the contents of a `debug.log` or `config.log` file. Raw text or a link to a pastebin type site are preferred. -->
