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A374386
a(n) is the minimal determinant of an n X n symmetric Toeplitz matrix having 0 on the main diagonal and all the first n-1 primes off-diagonal.
5
1, 0, -4, 24, -324, -15164, -1453072, -161765904, -37905894000, -1376219654680, -718058901423168, -163742479201610036
OFFSET
0,3
EXAMPLE
a(5) = -15164:
[0, 2, 7, 3, 5]
[2, 0, 2, 7, 3]
[7, 2, 0, 2, 7]
[3, 7, 2, 0, 2]
[5, 3, 7, 2, 0]
MATHEMATICA
a[n_]:=Min[Table[Det[ToeplitzMatrix[Join[{0}, Part[Permutations[Prime[Range[n-1]]], i]]]], {i, (n-1)!}]]; Join[{1}, Array[a, 10]]
CROSSREFS
Cf. A374387 (maximal), A374388 (maximal absolute value), A374389 (minimal nonzero absolute value).
Cf. A374068 (minimal permanent), A374390 (maximal permanent).
Sequence in context: A219118 A005756 A206239 * A361054 A196687 A185457
KEYWORD
sign,hard,more
AUTHOR
Stefano Spezia, Jul 07 2024
EXTENSIONS
a(11) from Giorgos Kalogeropoulos, Jul 10 2024
STATUS
approved