Man pages matching name ctanh in section 3:

ctanh.3.de	debian 10 / manpages-de-dev
ctanh.3.en	debian 10 / manpages-dev
ctanh.3.ja	debian 10 / manpages-ja-dev
ctanh.3.pl	debian 10 / manpages-pl-dev
ctanh.3.de	debian 11 / manpages-de-dev
ctanh.3.en	debian 11 / manpages-dev
ctanh.3.fr	debian 11 / manpages-fr-dev
ctanh.3.ja	debian 11 / manpages-ja-dev
ctanh.3.pl	debian 11 / manpages-pl-dev
ctanh.3.de	debian 12 / manpages-de-dev
ctanh.3.en	debian 12 / manpages-dev
ctanh.3.fr	debian 12 / manpages-fr-dev
ctanh.3.ja	debian 12 / manpages-ja-dev
ctanh.3.pl	debian 12 / manpages-pl-dev