A364231 a(n) is the number of n X n nonsingular symmetric Toeplitz matrices using all the integers 1, 2, ..., n.

1, 2, 6, 24, 120, 718, 5005, 40274, 362604, 3627915, 39909566, 478991256

Offset

1,2

Links

Table of n, a(n) for n=1..12.

Wikipedia, Toeplitz Matrix

Mathematica

a[n_]:=Count[Table[MatrixRank[ToeplitzMatrix[Part[Permutations[Range[n]], i]]], {i, n!}], n]; Array[a, 8]

Crossrefs

Right diagonal of A364230.

Cf. A350953 (minimal determinant), A350954 (maximal determinant), A351019 (minimal permanent), A351020 (maximal permanent), A356865 (minimal nonzero absolute value determinant).

Sequence in context: A226437 A224287 A248838 * A364234 A052398 A047890

Adjacent sequences: A364228 A364229 A364230 * A364232 A364233 A364234

Keyword

nonn,hard,more

Author

Stefano Spezia, Jul 14 2023

Extensions

a(10)-a(12) from Andrew Howroyd, Dec 30 2023

Status

approved