2551500

Appears in sequences

• Number of primitive (aperiodic) reversible strings with n beads using exactly five different colors.at n=9A056321
• Denominator of the rational coefficient in the main term in the dynamical analog of Mertens's theorem for a full n-dimensional shift, n >= 2.at n=4A159282
• a(n) = (2n)! * (n+1)! / 2^(2n).at n=5A202689