A374619 a(n) is the number of distinct values of the determinant 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, 1, 2, 6, 22, 120, 717, 5039, 40312, 362874

Offset

0,4

Links

Table of n, a(n) for n=0..10.

Wikipedia, Toeplitz Matrix.

Formula

a(n) <= (n-1)! for n > 0.

Mathematica

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

Crossrefs

Cf. A000142, A369832.

Cf. A374340, A374341, A374342, A374343.

Cf. A374617, A374618, A374620, A374621.

Sequence in context: A352413 A101042 A171339 * A032266 A095856 A180367

Adjacent sequences: A374616 A374617 A374618 * A374620 A374621 A374622

Keyword

nonn,hard,more

Author

Stefano Spezia, Jul 14 2024

Status

approved