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Let J_n be an n X n matrix which contains 1's only, I = I_n be the n X n identity matrix, and P = P_n be the incidence matrix of the cycle (1,2,3,...,n). Then a(n) is the number of (0,1,2) n X n matrices A <= 2(J_n - I - P) with exactly one 1 and one 2 in every row and column.
4

%I #9 Jan 30 2021 01:29:24

%S 0,2,36,1462,83600,5955474

%N Let J_n be an n X n matrix which contains 1's only, I = I_n be the n X n identity matrix, and P = P_n be the incidence matrix of the cycle (1,2,3,...,n). Then a(n) is the number of (0,1,2) n X n matrices A <= 2(J_n - I - P) with exactly one 1 and one 2 in every row and column.

%D V. S. Shevelev, Development of the rook technique for calculating the cyclic indicators of (0,1)-matrices, Izvestia Vuzov of the North-Caucasus region, Nature sciences 4 (1996), 21-28 (in Russian).

%D S. E. Grigorchuk, V. S. Shevelev, An algorithm of computing the cyclic indicator of couples discordant permutations with restricted position, Izvestia Vuzov of the North-Caucasus region, Nature sciences 3 (1997), 5-13 (in Russian).

%Y Cf. A001499, A007107, A082491, A000186, A174564.

%K nonn,more,uned

%O 3,2

%A _Vladimir Shevelev_, Mar 23 2010