A257625 → x ↦ x+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(P_{n}(x) = \left(-3\,x + 6\,n + 6\,n x\right)\,P_{n-1}(x) + \left(-6\,x - 6\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | |||||||
| 1 | 6 | 3 | 9 | ||||||
| 2 | 72 | 72 | 9 | 153 | |||||
| 3 | 1296 | 1944 | 702 | 27 | 3969 | ||||
| 4 | 31104 | 62208 | 37584 | 6480 | 81 | 137457 | |||
| 5 | 933120 | 2332800 | 1982880 | 641520 | 58806 | 243 | 5949369 | ||
| 6 | 33592320 | 100776960 | 110574720 | 53187840 | 10328472 | 530712 | 729 | 308991753 | |
| 7 | 1410877440 | 4938071040 | 6642881280 | 4262025600 | 1302857136 | 161295624 | 4780782 | 2187 | 18722791089 |
Compute more
?
Technical details
- Node id
n-7bc03246f43906fd· revision 0 · JSON- Definition source
derived:shift_x_plus_one- Fingerprint
f6-2a2e8db5a042c827
Observed on the stored rows ?
- Degrees: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 (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: 6, 3; 2: 72, 72, 9; 3: 1296, 1944, 702, 27; 4: 31104, 62208, 37584, 6480, 81; 5: 933120, 2332800, 1982880, 641520, 58806, 243; 6: 33592320, 100776960, 110574720, 53187840, 10328472, 530712, 729; 7: 1410877440, 4938071040, 6642881280, 4262025600, 1302857136, 161295624, 4780782, 2187; 8: 67722117120, 270888468480, 431728496640, 347075850240, 146343262464, 30263321088, 2476803744, 43040160, 6561; 9: 3656994324480, 16456474460160, 30322577940480, 29332141977600, 15843800931840, 4677587792640, 680112210240, 37668538080, 387400806, 19683;
%F FormulaThe row polynomials satisfy P(n,x) = (6*n+(6*n-3)*x)*P(n-1,x) - (6*x+6*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[(6*n + (6*n - 3)*x)*P[n - 1, x] - (6*x + 6*x^2)*D[P[n - 1, x], x]];
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] = (6*n + (6*n - 3)*x)*v[i - 1] - (6*x + 6*x^2)*deriv(v[i - 1], x)); 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)
- Interlacing of consecutive rows? Rows P_(m-1), P_m interlace (weak, unordered) for every m ≥ 1
Proof chains ? JSON
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
Related ?
Same fingerprint ?
- A060187 → x ↦ x+1
- type_b_eulerian → x ↦ x+1
- A060187 → x ↦ x/(x+1)
- type_b_eulerian → x ↦ x/(x+1)
- A257612 → x ↦ x+1
- A257612 → x ↦ x/(x+1)
- A257625 → x ↦ x/(x+1)
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