find ina_m_15

It seems you may be referencing a specific mathematical or computational sequence or function designated as "ina_m_15." However, the term "ina_m_15" does not appear to correspond with a recognized formula, sequence, or pattern in mathematics or programming by default. Could you please provide more context or specify the domain in which you're using this term? For example, are you looking for a specific notation in algebra, a programming function, or something else entirely? That way, I can assist you more effectively!