A374345 - OEIS

A374345

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

1, 1, 5, 59, 2454, 177998, 36960008, 7670953632, 2822399976144, 1061085324952592, 598646324654443008

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OFFSET

0,3

LINKS

EXAMPLE

a(5) = 177998:

[1, 7, 5, 3, 2]

[7, 1, 7, 5, 3]

[5, 7, 1, 7, 5]

[3, 5, 7, 1, 7]

[2, 3, 5, 7, 1]

MATHEMATICA

a[n_]:=Max[Table[Permanent[ToeplitzMatrix[Join[{1}, Part[Permutations[Prime[Range[n-1]]], i]]]], {i, (n-1)!}]]; Join[{1}, Array[a, 10]]

CROSSREFS

KEYWORD

nonn,hard,more

AUTHOR

STATUS

approved