165550domain: NAppears in sequencesNumber of numbers below 10^n with nonzero multiplicative digital root 5.at n=6A051825Number of factor-free Dyck words with slope 7/2 and length 9n.at n=5A274244Least n-gonal number that can be written as a product of two or more smaller n-gonal numbers, or 0 if no such number exists.at n=17A374371