A078812 → x ↦ x+1 → D+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(-8 + 6\,x + 2\,x^{2} + 12\,n - 6\,n x - 2\,n x^{2} - 6\,n^{2} + 2\,n^{3}\right)\,P_{n}(x) = \left(4\,n - 12\,n x - 7\,n x^{2} - n x^{3} + 3\,n^{3} + n^{3} x\right)\,P_{n-1}(x) + \left(-10 - 37\,x - 37\,x^{2} - 11\,x^{3} - x^{4} - 5\,n - 6\,n x - n x^{2} + 5\,n^{2} + 6\,n^{2} x + n^{2} x^{2}\right)\,P_{n-1}'(x)\)
\(P_{1}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | x9 | x10 | x11 | x12 | x13 | x14 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | ||||||||||||||
| 2 | 4 | 1 | 5 | |||||||||||||
| 3 | 14 | 8 | 1 | 23 | ||||||||||||
| 4 | 46 | 43 | 12 | 1 | 102 | |||||||||||
| 5 | 145 | 192 | 87 | 16 | 1 | 441 | ||||||||||
| 6 | 444 | 768 | 492 | 146 | 20 | 1 | 1871 | |||||||||
| 7 | 1331 | 2856 | 2391 | 1000 | 220 | 24 | 1 | 7823 | ||||||||
| 8 | 3926 | 10085 | 10488 | 5725 | 1770 | 309 | 28 | 1 | 32332 | |||||||
| 9 | 11434 | 34264 | 42731 | 28968 | 11670 | 2856 | 413 | 32 | 1 | 132369 | ||||||
| 10 | 32960 | 112991 | 164676 | 133918 | 66948 | 21315 | 4312 | 532 | 36 | 1 | 537689 | |||||
| 11 | 94211 | 363864 | 607686 | 577888 | 346465 | 136752 | 35938 | 6192 | 666 | 40 | 1 | 2169703 | ||||
| 12 | 267384 | 1149312 | 2165928 | 2362100 | 1656140 | 783538 | 255024 | 57006 | 8550 | 815 | 44 | 1 | 8705842 | |||
| 13 | 754309 | 3572472 | 7503558 | 9241600 | 7432765 | 4111488 | 1603014 | 443376 | 86175 | 11440 | 979 | 48 | 1 | 34761225 | ||
| 14 | 2116936 | 10955329 | 25386996 | 34877518 | 31691340 | 20108727 | 9163248 | 3034032 | 729036 | 125290 | 14916 | 1158 | 52 | 1 | 138204579 | |
| 15 | 5914310 | 33209576 | 84190861 | 127714248 | 129504078 | 92847240 | 48523377 | 18769872 | 5395731 | 1145496 | 176385 | 19032 | 1352 | 56 | 1 | 547411615 |
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Technical details
- Node id
n-2c3a50cd6c534a8f· revision 0 · JSON- Definition source
derived:one_plus_derivative- Fingerprint
f6-ab0d65133ac4f36a
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 -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 = 1, …, ascending powers of x
%e ExampleTriangle begins: 1: 1; 2: 4, 1; 3: 14, 8, 1; 4: 46, 43, 12, 1; 5: 145, 192, 87, 16, 1; 6: 444, 768, 492, 146, 20, 1; 7: 1331, 2856, 2391, 1000, 220, 24, 1; 8: 3926, 10085, 10488, 5725, 1770, 309, 28, 1; 9: 11434, 34264, 42731, 28968, 11670, 2856, 413, 32, 1; 10: 32960, 112991, 164676, 133918, 66948, 21315, 4312, 532, 36, 1;
%F FormulaThe row polynomials satisfy (2*n^3-6*n^2+12*n-8-(6*n-6)*x-(2*n-2)*x^2)*P(n,x) = (3*n^3+4*n+(n^3-12*n)*x-7*n*x^2-n*x^3)*P(n-1,x) + (5*n^2-5*n-10+(6*n^2-6*n-37)*x+(n^2-n-37)*x^2-11*x^3-x^4)*d/dx P(n-1,x) for n >= 2, with P(1,x) = 1.
%t MathematicaP[1, x_] := 1;
P[n_, x_] := P[n, x] = Expand[Together[((3*n^3 + 4*n + (n^3 - 12*n)*x - 7*n*x^2 - n*x^3)*P[n - 1, x] + (5*n^2 - 5*n - 10 + (6*n^2 - 6*n - 37)*x + (n^2 - n - 37)*x^2 - 11*x^3 - x^4)*D[P[n - 1, x], x])/(2*n^3 - 6*n^2 + 12*n - 8 - (6*n - 6)*x - (2*n - 2)*x^2)]];
Table[CoefficientList[P[n, x], x], {n, 1, 10}] // Flatten%o PARI/GPP(N) = {my(v = vector(N)); v[1] = 1; for(n = 2, N, my(i = n); v[i] = ((3*n^3 + 4*n + (n^3 - 12*n)*x - 7*n*x^2 - n*x^3)*v[i - 1] + (5*n^2 - 5*n - 10 + (6*n^2 - 6*n - 37)*x + (n^2 - n - 37)*x^2 - 11*x^3 - x^4)*deriv(v[i - 1], x))/(2*n^3 - 6*n^2 + 12*n - 8 - (6*n - 6)*x - (2*n - 2)*x^2)); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i, v[i])))};
T(10)polytool c48629374597
Properties
- Real-rooted? Every row P_n, n ≥ 1, is zero or real-rooted with all roots in (−∞, 0]
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Coefficients of one sign?
Every nonzero row, n ≥ 1: 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 ≥ 1, 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 ≥ 2
Proof chains ? JSON
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Laguerre’s theorem on differential operators [SP14] polytool ? step ›
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from
basis_map_A007318 of Triangle read by rows: T(n, k) = binomial(n+k-1, 2*k-1).?
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Geometric basis map (elementary) polytool ? step ›
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from
basis_map_A007318 of Triangle read by rows: T(n, k) = binomial(n+k-1, 2*k-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
- [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