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.

A349226 Triangle read by rows. Row n gives the coefficients of Product_{k=0..n} (x - k^k) expanded in decreasing powers of x, with row 0 = {1}.

Original entry on oeis.org

1, 1, -1, 1, -2, 1, 1, -6, 9, -4, 1, -33, 171, -247, 108, 1, -289, 8619, -44023, 63340, -27648, 1, -3413, 911744, -26978398, 137635215, -197965148, 86400000, 1, -50070, 160195328, -42565306462, 1258841772303, -6421706556188, 9236348345088, -4031078400000
Offset: 0

Views

Author

Thomas Scheuerle, Jul 07 2022

Keywords

Comments

Let M be an n X n matrix filled by binomial(i*j, i) with rows and columns j = 1..n, k = 1..n; then its determinant equals unsigned T(n, n). Can we find a general formula for T(n+m, n) based on determinants of matrices and binomials?

Examples

			The triangle begins:
  1;
  1,    -1;
  1,    -2,      1;
  1,    -6,      9,        -4;
  1,   -33,    171,      -247,       108;
  1,  -289,   8619,    -44023,     63340,     -27648;
  1, -3413, 911744, -26978398, 137635215, -197965148, 86400000;
  ...
Row 4: x^4-33*x^3+171*x^2-247*x+108 = (x-1)*(x-1^1)*(x-2^2)*(x-3^3).
		

Crossrefs

Cf. A008276 (The Stirling numbers of the first kind in reverse order).
Cf. A039758 (Coefficients for polynomials with roots in odd numbers).
Cf. A355540 (Coefficients for polynomials with roots in factorials).

Programs

  • PARI
    T(n, k) = polcoeff(prod(m=0, n-1, (x-m^m)), n-k);

Formula

T(n, 0) = 1.
T(n, 1) = -A062970(n).
T(n, 2) = Sum_{m=0..n-1} A062970(m)*m^m.
T(n, k) = Sum_{m=0..n-1} -T(m, k-1)*m^m.
T(n, n) = (-1)^n*A002109(n).