274878955520domain: NAppears in sequencesNumbers k such that A007947(k) = A007947(m+1) and A007947(m) = A007947(k+1), where k > m.at n=20A088966a(n) = n^7*(n^6 + 1)/2.at n=8A168663a(n) = 4^n + 2^(n+1).at n=19A242985