A374278 - OEIS

A374278

a(n) is the maximal permanent of an n X n symmetric Toeplitz matrix having 1 on the main diagonal and all the integers 1, 2, ..., n-1 off-diagonal.

1, 1, 2, 18, 389, 14284, 798322, 62490160, 6519511313, 873036867840, 145856387327074

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OFFSET

0,3

LINKS

EXAMPLE

a(5) = 14284:

[1, 4, 3, 2, 1]

[4, 1, 4, 3, 2]

[3, 4, 1, 4, 3]

[2, 3, 4, 1, 4]

[1, 2, 3, 4, 1]

MATHEMATICA

a[0]=1; a[n_]:=Max[Table[Permanent[ToeplitzMatrix[Join[{1}, Part[Permutations[Range[n - 1]], i]]]], {i, (n-1)!}]]; Array[a, 11, 0]

CROSSREFS

KEYWORD

nonn,hard,more

AUTHOR

STATUS

approved