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%I #8 Mar 30 2012 18:58:08
%S 2,5,5,8,4,8,11,7,7,11,14,10,6,10,14,17,13,9,9,13,17,20,16,12,8,12,16,
%T 20,23,19,15,11,11,15,19,23,26,22,18,14,10,14,18,22,26,29,25,21,17,13,
%U 13,17,21,25,29,32,28,24,20,16,12,16,20,24,28,32,35,31,27,23
%N Symmetric matrix given by f(i,j)=max(3i-j,3j-i).
%e Northwest corner:
%e 2....5....8....11...14...17
%e 5....4....7....10...13...16
%e 8....7....6....9....12...15
%e 11...10...9....8....11...14
%e 14...13...12...11...10...13
%t f[i_, j_] := Max[3 i - j, 3 j - i];
%t m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
%t TableForm[m[8]] (* 8x8 principal submatrix *)
%t Flatten[Table[f[i, n + 1 - i],
%t {n, 1, 12}, {i, 1, n}]] (* A204237 *)
%t Table[Det[m[n]], {n, 1, 22}] (* A204238 *)
%t Permanent[m_] :=
%t With[{a = Array[x, Length[m]]},
%t Coefficient[Times @@ (m.a), Times @@ a]];
%t Table[Permanent[m[n]], {n, 1, 14}] (* A204239 *)
%Y Cf. A204238, A204239.
%K nonn,tabl
%O 1,1
%A _Clark Kimberling_, Jan 13 2012
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