1644167168domain: NAppears in sequencesa(n) = (2*n + 1) * 2^(n + 1).at n=24A118417a(n) = n-th integer from among those positive integers with an exponent of n in their prime-factorizations.at n=24A123904Maximum determinant of an n X n circulant (1,-1)-matrix.at n=15A215723