Man pages matching name algorithm::checkdigits in section 3pm:

Algorithm::CheckDigits.3pm.en	debian 10 / libalgorithm-checkdigits-perl
Algorithm::CheckDigits.3pm.en	debian 11 / libalgorithm-checkdigits-perl
Algorithm::CheckDigits.3pm.en	debian 12 / libalgorithm-checkdigits-perl