How I can make a more efficient bruteforce attack?

[leantw1ce]

Hi, first of all my english isn't good enough, so sorry about that. I want to know if it's possible to specify hashcat to do a bruteforce to a password that has the same word twice. Ej:  demos1234demos1234. 
Thanks in advance for any help you are able to provide.

[royce]

Take a look at

https://hashcat.net/wiki/doku.php?id=rule_based_attack

The 'd' rule function repeats a word.