Real-rooted atlas

A304236 → basis A007318 → D

nonnegative coefficients

Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernel

Recurrence

\(\left(-2 + n\right)\,P_{n}(x) = \left(-19 - 18\,x + 7\,n + 6\,n x\right)\,P_{n-1}(x) + \left(-13 - 25\,x - 12\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 0\)
\(P_{1}(x) = 0\)
\(P_{2}(x) = 3\)

Rows ?

nx0x1x2Pn(1)
00
10
233
366
4271845
56654120
620427081555
75228283241674

All 15 rows

Technical details
Node id
n-adac1d41cd2192d2 · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-a9c669ac8d6ddada

Observed on the stored rows ?

  • Degrees: -1, -1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6 (half affine: slope 1, intercept -2)
  • Palindromic rows: no
  • γ-positive (gamma_positive): no
  • Nonnegative coefficients (nonn): yes
  • Only rational roots (rr_by_factors: every nonzero row is a product of linear factors over ℚ): no

Matches ?

No OEIS matches.

Submission text ?

Atlas rows n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:    0;
  1:    0;
  2:    3;
  3:    6;
  4:   27,   18;
  5:   66,   54;
  6:  204,  270,   81;
  7:  522,  828,  324;
  8: 1425, 2862, 1782,  324;
  9: 3642, 8478, 6480, 1620;
%F Formula
The row polynomials satisfy (n-2)*P(n,x) = (7*n-19+(6*n-18)*x)*P(n-1,x) - (13+25*x+12*x^2)*d/dx P(n-1,x) for n >= 3, with P(0,x) = 0, P(1,x) = 0, P(2,x) = 3.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := 0;
P[2, x_] := 3;
P[n_, x_] := P[n, x] = Expand[Together[((7*n - 19 + (6*n - 18)*x)*P[n - 1, x] - (13 + 25*x + 12*x^2)*D[P[n - 1, x], x])/(n - 2)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 0; v[2] = 0; v[3] = 3; for(n = 3, N, my(i = n + 1); v[i] = ((7*n - 19 + (6*n - 18)*x)*v[i - 1] - (13 + 25*x + 12*x^2)*deriv(v[i - 1], x))/(n - 2)); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i - 1, v[i])))};
T(9)

polytool c48629374597

Properties

Proof chains ? JSON

Same fingerprint ?

References

  1. [LW07] Lily L. Liu and Yi Wang. A unified approach to polynomial sequences with only real zeros. Advances in Applied Mathematics, 38(4):542–560, May 2007. doi:10.1016/j.aam.2006.02.003
  2. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.