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Number of ways to place 5 non-attacking wazirs on an n X n toroidal board.
8

%I #10 Sep 12 2015 11:00:27

%S 0,0,0,128,6745,100332,754453,3830016,15038541,49207020,140410699,

%T 360001152,846775007,1855033964,3828109545,7507096576,14087087961,

%U 25436160108,44395753647,75184958080,123935571963,199389702380,313797119069,484055619840,733144325125

%N Number of ways to place 5 non-attacking wazirs on an n X n toroidal board.

%C Wazir is a leaper [0,1].

%H V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, p.402

%F a(n) = n^2*(n^8 - 50n^6 + 995n^4 - 9370n^2 + 35424)/120, n>=6.

%F G.f.: -x^4 * (10x^12 - 110x^11 + 685x^10 - 2771x^9 + 6946x^8 - 9350x^7 + 1710x^6 + 15214x^5 - 21392x^4 + 656x^3 + 33177x^2 + 5337x + 128)/(x-1)^11.

%Y Cf. A172228, A201236, A201237, A201238, A201240, A201241, A201242.

%K nonn

%O 1,4

%A _Vaclav Kotesovec_, Nov 28 2011