2091817

Appears in sequences

• Number of perfect matchings in graph C_{9} X P_{2n}.at n=3A028480
• Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 1000-1101-0111 pattern in any orientation.at n=19A147166
• Number of perfect matchings in the P_6 X C_n graph.at n=6A254611
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals, where T(n,k) = Product_{a=1..n} Product_{b=1..k} (4*sin(a*Pi/(2*n+1))^2 + 4*cos(b*Pi/(2*k+1))^2).at n=32A340476