250905600domain: NAppears in sequencesMaximum number of binary strings with symmetrically partitioned n 1's and n 0's, counted up to isomorphism.at n=20A250029a(n) is the least integer m such that A047994(m) = ((n-2)/n)*m where A047994 is the unitary totient function, or 0 if there is no such m.at n=30A319313