A207606 → basis A013610 → D
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(-18 + 54\,x - 12\,n + 90\,n x + 6\,n^{2} + 36\,n^{2} x\right)\,P_{n}(x) = \left(-99 + 189\,x + 324\,x^{2} - 6\,n + 252\,n x + 270\,n x^{2} + 9\,n^{2} + 63\,n^{2} x + 54\,n^{2} x^{2}\right)\,P_{n-1}(x) + \left(-5 + 42\,x + 207\,x^{2} + 108\,x^{3} + 5\,n + 48\,n x + 117\,n x^{2} + 54\,n x^{3}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 33 + 36\,x\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 33 | 36 | 69 | |||||||
| 1 | 132 | 306 | 162 | 600 | ||||||
| 2 | 465 | 1674 | 1863 | 648 | 4650 | |||||
| 3 | 1530 | 7506 | 12960 | 9396 | 2430 | 33822 | ||||
| 4 | 4824 | 30024 | 70794 | 79380 | 42525 | 8748 | 236295 | |||
| 5 | 14772 | 111510 | 334530 | 511920 | 422820 | 179334 | 30618 | 1605504 | ||
| 6 | 44283 | 393138 | 1434591 | 2794500 | 3145635 | 2051406 | 719523 | 104976 | 10688052 | |
| 7 | 130620 | 1333602 | 5738364 | 13609944 | 19493460 | 17299170 | 9307872 | 2781864 | 354294 | 70049190 |
Compute more
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Technical details
- Node id
n-93da713ca5d063cd· revision 0 · JSON- Definition source
derived:derivative- Fingerprint
f6-c8dfaec64c280b41
Observed on the stored rows ?
- Degrees: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 (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 ExampleTriangle begins: 0: 33, 36; 1: 132, 306, 162; 2: 465, 1674, 1863, 648; 3: 1530, 7506, 12960, 9396, 2430; 4: 4824, 30024, 70794, 79380, 42525, 8748; 5: 14772, 111510, 334530, 511920, 422820, 179334, 30618; 6: 44283, 393138, 1434591, 2794500, 3145635, 2051406, 719523, 104976; 7: 130620, 1333602, 5738364, 13609944, 19493460, 17299170, 9307872, 2781864, 354294; 8: 380415, 4391388, 21781710, 60988788, 106372035, 120022560, 87751188, 40153320, 10451673, 1180980; 9: 1096596, 14123052, 79368012, 256483260, 528330600, 725707836, 674024652, 418539312, 166518180, 38381850, 3897234;
%F FormulaThe row polynomials satisfy (6*n^2-12*n-18+(36*n^2+90*n+54)*x)*P(n,x) = (9*n^2-6*n-99+(63*n^2+252*n+189)*x+(54*n^2+270*n+324)*x^2)*P(n-1,x) + (5*n-5+(48*n+42)*x+(117*n+207)*x^2+(54*n+108)*x^3)*d/dx P(n-1,x) for n >= 1, with P(0,x) = 33 + 36*x.
%t MathematicaP[0, x_] := 33 + 36*x;
P[n_, x_] := P[n, x] = Expand[Together[((9*n^2 - 6*n - 99 + (63*n^2 + 252*n + 189)*x + (54*n^2 + 270*n + 324)*x^2)*P[n - 1, x] + (5*n - 5 + (48*n + 42)*x + (117*n + 207)*x^2 + (54*n + 108)*x^3)*D[P[n - 1, x], x])/(6*n^2 - 12*n - 18 + (36*n^2 + 90*n + 54)*x)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten%o PARI/GPP(N) = {my(v = vector(N + 1)); v[1] = 33 + 36*x; for(n = 1, N, my(i = n + 1); v[i] = ((9*n^2 - 6*n - 99 + (63*n^2 + 252*n + 189)*x + (54*n^2 + 270*n + 324)*x^2)*v[i - 1] + (5*n - 5 + (48*n + 42)*x + (117*n + 207)*x^2 + (54*n + 108)*x^3)*deriv(v[i - 1], x))/(6*n^2 - 12*n - 18 + (36*n^2 + 90*n + 54)*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 (−∞, 0]
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Coefficients of one sign?
Every nonzero row, n ≥ 0: the coefficients of P_n have one sign
derived from Laguerre’s theorem on differential operators
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Hadamard kernel (Malo)?
Rows P_n, n ≥ 0, are Hadamard kernels (preserve real-rootedness)
derived from Laguerre’s theorem on differential operators
- Interlacing of consecutive rows? Rows P_(m-1), P_m interlace (weak, unordered) for every m ≥ 1
Proof chains ? JSON
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Laguerre’s theorem on differential operators [SP14] polytool ? step ›
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from
basis_map_A013610 of Triangle of coefficients of polynomials u(n,x) jointly generated with A207607; see the Formula sec…?
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Geometric basis map (elementary) polytool ? step ›
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from
Triangle of coefficients of polynomials u(n,x) jointly generated with A207607; see the Formula section.?
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
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from
Triangle of coefficients of polynomials u(n,x) jointly generated with A207607; see the Formula section.?
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Geometric basis map (elementary) polytool ? step ›
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from
basis_map_A013610 of Triangle of coefficients of polynomials u(n,x) jointly generated with A207607; see the Formula sec…?
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
- [SP14] J Schur and G Polya. Über zwei Arten von Faktorenfolgen in der Theorie der algebraischen Gleichungen. J. Reine Angew. Math., 1914.
- [Sze39] G. Szegő. Orthogonal Polynomials. Colloquium publications, American Mathematical Society, 1939. doi:10.1090/coll/023