334488domain: NAppears in sequencesNumbers k such that k and k^2 use only the digits 1, 2, 3, 4 and 8.at n=39A136971Number of length n+3 0..4 arrays with no four elements in a row with pattern abab (with a!=b) and new values 0..4 introduced in 0..4 order.at n=7A243040