A169803 → basis A013610 → D

nonnegative coefficients

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

Recurrence

\(\left(-3 + 3\,n\right)\,P_{n}(x) = \left(-12 - 36\,x + 9\,n + 18\,n x\right)\,P_{n-1}(x) + \left(-5 - 27\,x - 36\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 0\)
\(P_{1}(x) = 3\)

Rows ?

nx0x1x2x3Pn(1)
00
133
266
3151833
4305484
56016281303
6114396324834
721391811343242589
Technical details
Node id
n-79e1184c488cf566 · revision 0 · JSON
Definition source
derived:derivative
Fingerprint
f6-b3025a17dcc529d7

Observed on the stored rows ?

  • Degrees: -1, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6 (half affine: slope 1, intercept -1)
  • 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:   3;
  2:   6;
  3:  15,   18;
  4:  30,   54;
  5:  60,  162,   81;
  6: 114,  396,  324;
  7: 213,  918, 1134,  324;
  8: 390, 1998, 3240, 1620;
  9: 705, 4194, 8505, 6480, 1215;
%F Formula
The row polynomials satisfy (3*n-3)*P(n,x) = (9*n-12+(18*n-36)*x)*P(n-1,x) - (5+27*x+36*x^2)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 0, P(1,x) = 3.
%t Mathematica
P[0, x_] := 0;
P[1, x_] := 3;
P[n_, x_] := P[n, x] = Expand[Together[((9*n - 12 + (18*n - 36)*x)*P[n - 1, x] - (5 + 27*x + 36*x^2)*D[P[n - 1, x], x])/(3*n - 3)]];
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] = 3; for(n = 2, N, my(i = n + 1); v[i] = ((9*n - 12 + (18*n - 36)*x)*v[i - 1] - (5 + 27*x + 36*x^2)*deriv(v[i - 1], x))/(3*n - 3)); 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. [MW08] Shi-Mei Ma and Yi Wang. q-Eulerian polynomials and polynomials with only real zeros. The Electronic Journal of Combinatorics, 15(1):Research Paper 17, January 2008. doi:10.37236/741
  3. [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.