99297793441domain: NAppears in sequencesa(n) is the permanent of the unipotent Sylvester-Kac tridiagonal matrix of order n having main diagonal [0, 2, ..., 2*(n-1)], superdiagonal [1, 2, ..., n-1], and [subdiagonal 1-n, 2-n, ..., -1].at n=12A390821