2128680domain: NAppears in sequencesa(n) = sinh(2*arcsinh(n))^2 = 4*n^2*(n^2 + 1).at n=27A173116Number of elements of order n in the simple unitary group U3(9).at n=15A284980Number of elements of order n in the simple unitary group U3(9).at n=19A284980p-INVERT of the odd positive integers, where p(S) = 1 + S - 2 S^2.at n=14A292491