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 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, 1, 2, 18, 389, 14284, 798322, 62490160, 6519511313, 873036867840, 145856387327074 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Table of n, a(n) for n=0..10. Wikipedia, Toeplitz Matrix. 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 Cf. A351020, A374139, A374140 (minimal). Cf. A374239, A374240, A374241, A374242. Sequence in context: A226837 A152684 A201732 * A260656 A141074 A351052 Adjacent sequences: A374275 A374276 A374277 * A374279 A374280 A374281 KEYWORD nonn,hard,more AUTHOR Stefano Spezia, Jul 02 2024 STATUS approved

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Last modified August 11 01:05 EDT 2024. Contains 375059 sequences. (Running on oeis4.)