A103327 → basis A013609 → basis A007318
nonnegative coefficients
Proved for all n all roots real, in (−∞, −1]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(-1 + 2\,n\right)\,P_{n}(x) = \left(-14 - 10\,x + 20\,n + 12\,n x\right)\,P_{n-1}(x) + \left(-12 - 20\,x - 8\,x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | |||||||
| 1 | 6 | 2 | 8 | ||||||
| 2 | 44 | 32 | 4 | 80 | |||||
| 3 | 328 | 376 | 120 | 8 | 832 | ||||
| 4 | 2448 | 3840 | 2016 | 384 | 16 | 8704 | |||
| 5 | 18272 | 36384 | 26688 | 8640 | 1120 | 32 | 91136 | ||
| 6 | 136384 | 329216 | 310464 | 142848 | 32320 | 3072 | 64 | 954368 | |
| 7 | 1017984 | 2887552 | 3329664 | 1991040 | 649600 | 110208 | 8064 | 128 | 9994240 |
Compute more
?
Other recurrences
Image under the basis map A007318 · proved equal for all n (proof step)
\(P_{n}(x) = \left(-4 - 8\,x - 4\,x^{2}\right)\,P_{n-2}(x) + \left(8 + 4\,x\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = 6 + 2\,x\)
Technical details
- Node id
n-2b6c5dd961f03a94· revision 0 · JSON- Definition source
derived:shift_x_plus_onederived:basis_map_A007318(equal bye-c00c60332ef216a6)- Fingerprint
f6-935c57c7e92571a4
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, 2; 2: 44, 32, 4; 3: 328, 376, 120, 8; 4: 2448, 3840, 2016, 384, 16; 5: 18272, 36384, 26688, 8640, 1120, 32; 6: 136384, 329216, 310464, 142848, 32320, 3072, 64; 7: 1017984, 2887552, 3329664, 1991040, 649600, 110208, 8064, 128; 8: 7598336, 24764416, 33766400, 24875008, 10647040, 2637824, 351232, 20480, 256; 9: 56714752, 208814592, 328697856, 287913984, 152830976, 50088960, 9848832, 1062912, 50688, 512;
%F FormulaThe row polynomials satisfy (2*n-1)*P(n,x) = (20*n-14+(12*n-10)*x)*P(n-1,x) - (12+20*x+8*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[((20*n - 14 + (12*n - 10)*x)*P[n - 1, x] - (12 + 20*x + 8*x^2)*D[P[n - 1, x], x])/(2*n - 1)]];
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] = ((20*n - 14 + (12*n - 10)*x)*v[i - 1] - (12 + 20*x + 8*x^2)*deriv(v[i - 1], x))/(2*n - 1)); 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
- Real-rooted? Every row P_n, n ≥ 0, is zero or real-rooted with all roots in (−∞, 0]
Proof chains ? JSON
-
Geometric basis map (elementary) polytool ? step ›
-
from
basis_map_A013609 of Triangle read by rows: T(n,k) = binomial(2n+1, 2k+1).?
-
Geometric basis map (elementary) polytool ? step ›
-
-
from
basis_map_A013609 of Triangle read by rows: T(n,k) = binomial(2n+1, 2k+1).?
Related ?
Same fingerprint ?
References
- [Fav35] Jean Favard. Sur les polynômes de tchebicheff. C. R. Acad. Sci. Paris, 200:2052–2053, 1935.
- [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
- [Sze39] G. Szegő. Orthogonal Polynomials. Colloquium publications, American Mathematical Society, 1939. doi:10.1090/coll/023