A374283 - OEIS

A374283

a(n) is the maximal permanent of an n X n symmetric Toeplitz matrix having 0 on the main diagonal and all the integers 1, 2, ..., n-1 off-diagonal.

1, 0, 1, 8, 256, 9978, 600052, 49036950, 5286564352, 725724599636

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OFFSET

0,4

LINKS

EXAMPLE

a(5) = 9978:

[0, 4, 3, 2, 1]

[4, 0, 4, 3, 2]

[3, 4, 0, 4, 3]

[2, 3, 4, 0, 4]

[1, 2, 3, 4, 0]

MATHEMATICA

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

CROSSREFS

Cf. A085807 (minimal), A358327.

KEYWORD

nonn,hard,more

AUTHOR

STATUS

approved