cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A374240 a(n) is the maximal 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.

Original entry on oeis.org

1, 1, 0, 0, 40, 256, 12232, 526773, 8684025, 768561384, 28938090375, 1273675677456, 73821863714933, 7601760995500947, 527066887623562528
Offset: 0

Views

Author

Stefano Spezia, Jul 01 2024

Keywords

Examples

			a(5) = 256:
  [1, 4, 1, 2, 3]
  [4, 1, 4, 1, 2]
  [1, 4, 1, 4, 1]
  [2, 1, 4, 1, 4]
  [3, 2, 1, 4, 1]
		

Crossrefs

Cf. A374239 (minimal), A374241 (maximal absolute value), A374242 (minimal nonzero absolute value).

Programs

  • Mathematica
    a[0]=1; a[n_]:=Max[Table[Det[ToeplitzMatrix[Join[{1}, Part[Permutations[Range[n - 1]], i]]]], {i, (n-1)!}]]; Array[a, 11, 0]

Extensions

a(11)-a(14) from Lucas A. Brown, Oct 10 2024