140865domain: NAppears in sequencesa(n) = floor(sqrt(phi(w)*sigma(w)+w^2)), where w=10^n.at n=4A065550The ED3 array read by antidiagonals.at n=40A167572The fifth row of the ED3 array A167572.at n=4A167575a(n) is the number of distinct billiard words with length n on an alphabet of 3 symbols.at n=17A180238