cp's OEIS Frontend

A204424 Permanent of the n-th principal submatrix of A204423.

%I A204424 #9 Oct 24 2024 05:41:00
%S A204424 0,2,9,16,144,1032,5184,48816,530712,4188672,50015232,707802624,
%T A204424 7614259200,112586112000,1938416832000,26579819520000,469224244224000,
%U A204424 9509523337728000,158654296829952000,3261008730405888000
%N A204424 Permanent of the n-th principal submatrix of A204423.
%t A204424 f[i_, j_] := Mod[2 i + j, 3];
%t A204424 m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
%t A204424 TableForm[m[8]] (* 8x8 principal submatrix *)
%t A204424 Flatten[Table[f[i, n + 1 - i],
%t A204424   {n, 1, 14}, {i, 1, n}]]      (* A204423 *)
%t A204424 Permanent[m_] :=
%t A204424   With[{a = Array[x, Length[m]]},
%t A204424    Coefficient[Times @@ (m.a), Times @@ a]];
%t A204424 Table[Permanent[m[n]], {n, 1, 22}]  (* A204424 *)
%Y A204424 Cf. A204223, A204263.
%K A204424 nonn
%O A204424 1,2
%A A204424 _Clark Kimberling_, Jan 15 2012