A059344 → basis A013610 → x ↦ x+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(3\right)\,P_{n}(x) = \left(-21 - 18\,x + 24\,n + 18\,n x\right)\,P_{n-1}(x) + \left(-64 - 96\,x - 36\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | Pn(1) |
|---|---|---|---|---|---|
| 0 | 1 | 1 | |||
| 1 | 1 | 1 | |||
| 2 | 9 | 6 | 15 | ||
| 3 | 25 | 18 | 43 | ||
| 4 | 241 | 324 | 108 | 673 | |
| 5 | 1041 | 1500 | 540 | 3081 | |
| 6 | 10681 | 21690 | 14580 | 3240 | 50191 |
| 7 | 60649 | 131166 | 94500 | 22680 | 308995 |
Compute more
?
Other recurrences
Image under the basis map A007318 · proved equal for all n (proof step)
\(P_{n}(x) = \left(-8 - 6\,x + 8\,n + 6\,n x\right)\,P_{n-2}(x) + \left(1\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = 1\)
Technical details
- Node id
n-4a989671ed602e62· revision 0 · JSON- Definition source
derived:shift_x_plus_onederived:basis_map_A007318(equal bye-1351ade7aa9263fa)- Fingerprint
f6-cfbbc3d2c85fff77
Observed on the stored rows ?
- Degrees: 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7 (half affine: slope 1, intercept 0)
- 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 ExampleTriangle begins: 0: 1; 1: 1; 2: 9, 6; 3: 25, 18; 4: 241, 324, 108; 5: 1041, 1500, 540; 6: 10681, 21690, 14580, 3240; 7: 60649, 131166, 94500, 22680; 8: 658785, 1794408, 1821960, 816480, 136080; 9: 4540321, 13100184, 14165928, 6804000, 1224720;
%F FormulaThe row polynomials satisfy 3*P(n,x) = (24*n-21+(18*n-18)*x)*P(n-1,x) - (64+96*x+36*x^2)*d/dx P(n-1,x) for n >= 1, with P(0,x) = 1.
%t MathematicaP[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((24*n - 21 + (18*n - 18)*x)*P[n - 1, x] - (64 + 96*x + 36*x^2)*D[P[n - 1, x], x])/(3)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten%o PARI/GPP(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = ((24*n - 21 + (18*n - 18)*x)*v[i - 1] - (64 + 96*x + 36*x^2)*deriv(v[i - 1], x))/(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
- Real-rooted? Every row P_n, n ≥ 0, is zero or real-rooted with all roots in (−∞, -1]
- Coefficients of one sign? Every nonzero row, n ≥ 0: the coefficients of P_n have one sign
- Hadamard kernel (Malo)? Rows P_n, n ≥ 0, are Hadamard kernels (preserve real-rootedness)
- Real-rooted? Every row P_n, n ≥ 0, is zero or real-rooted with all roots in (−∞, 0]
- Interlacing of consecutive rows? Rows P_(m-1), P_m interlace (weak, unordered) for every m ≥ 1
Proof chains ? JSON
References
- [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