otp binary package in Ubuntu Bionic arm64

 otp creates key and password lists for verification and
 security purposes in a variety of formats. Keys can be of
 any length, consist of digits or letters (capital or lower
 case), and alphabetic passwords can either be entirely
 random (most secure) or obey the digraph statistics of
 English text (easier to remember when transcribing, but less
 secure).
 .
 For computer applications, for example one-time login
 passwords, otp can create a file containing the MD5
 signature of each of the generated keys. This permits the
 computer to verify keys without the need to store the keys in
 plaintext.

Source package