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A374239
a(n) is the minimal determinant of an n X n symmetric Toeplitz matrix having 1 on the main diagonal and all the integers 1, 2, ..., n-1 off-diagonal.
7
1, 1, 0, -1, 1, -545, -13805, -301184, -18551951, -352513176, -31451535983, -1209153784888, -87868166035113, -4204963833160760, -664087819207293468
OFFSET
0,6
LINKS
EXAMPLE
a(5) = -545:
[1, 1, 4, 2, 3]
[1, 1, 1, 4, 2]
[4, 1, 1, 1, 4]
[2, 4, 1, 1, 1]
[3, 2, 4, 1, 1]
MATHEMATICA
a[0]=1; a[n_]:=Min[Table[Det[ToeplitzMatrix[Join[{1}, Part[Permutations[Range[n - 1]], i]]]], {i, (n-1)!}]]; Array[a, 11, 0]
CROSSREFS
Cf. A374240 (maximal), A374241 (maximal absolute value), A374242 (minimal nonzero absolute value).
Sequence in context: A159626 A020259 A184379 * A353023 A053327 A252537
KEYWORD
sign,hard,more
AUTHOR
Stefano Spezia, Jul 01 2024
EXTENSIONS
a(11)-a(14) from Lucas A. Brown, Oct 10 2024
STATUS
approved