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 A204268 Permanent of the n-th principal submatrix of A204267. 3
 0, 1, 9, 16, 132, 1032, 5184, 51912, 530712, 4188672, 53529984, 707802624, 7614259200, 119716185600, 1938416832000, 26579819520000, 496487584512000, 9509523337728000, 158654296829952000, 3434389946233344000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS G. C. Greubel, Table of n, a(n) for n = 1..100 MATHEMATICA f[i_, j_] := Mod[i + j + 1, 3]; m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}] TableForm[m[8]] (* 8x8 principal submatrix *) Flatten[Table[f[i, n + 1 - i],   {n, 1, 14}, {i, 1, n}]]    (* A204267 *) Permanent[m_] :=   With[{a = Array[x, Length[m]]},    Coefficient[Times @@ (m.a), Times @@ a]]; Table[Permanent[m[n]], {n, 1, 22}]  (* A204268 *) CROSSREFS Cf. A204267. Sequence in context: A177171 A226232 A267088 * A075373 A072470 A053911 Adjacent sequences:  A204265 A204266 A204267 * A204269 A204270 A204271 KEYWORD nonn AUTHOR Clark Kimberling, Jan 15 2012 STATUS approved

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Last modified January 27 01:45 EST 2021. Contains 340443 sequences. (Running on oeis4.)