A232535 → basis A013610 → D+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(-19\,x + 6\,x^{2} - 9\,n + 30\,n x - 19\,n x^{2} + 6\,n x^{3} + 15\,n^{2} - 17\,n^{2} x + 12\,n^{2} x^{2} - 6\,n^{3} + 6\,n^{3} x\right)\,P_{n}(x) = \left(-36 - 144\,x - 74\,x^{2} + 69\,x^{3} - 18\,x^{4} + 24\,n + 125\,n x + 98\,n x^{2} - 129\,n x^{3} + 54\,n x^{4} + 36\,n^{2} + 49\,n^{2} x - 87\,n^{2} x^{2} + 108\,n^{2} x^{3} - 24\,n^{3} - 30\,n^{3} x + 54\,n^{3} x^{2}\right)\,P_{n-1}(x) + \left(-12\,x - 46\,x^{2} - 16\,x^{3} + 30\,x^{4} - 36\,x^{5} + 16\,n x^{2} + 24\,n x^{3} - 72\,n x^{4} + 12\,n^{2} x + 24\,n^{2} x^{2} - 36\,n^{2} x^{3}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | |||||||
| 1 | 9 | 6 | 15 | ||||||
| 2 | 54 | 96 | 27 | 177 | |||||
| 3 | 288 | 906 | 657 | 108 | 1959 | ||||
| 4 | 1440 | 6576 | 8820 | 3672 | 405 | 20913 | |||
| 5 | 6912 | 41568 | 83808 | 65772 | 18225 | 1458 | 217743 | ||
| 6 | 32256 | 241152 | 655488 | 790992 | 416826 | 83592 | 5103 | 2225409 | |
| 7 | 147456 | 1319424 | 4531968 | 7502976 | 6174144 | 2364390 | 362313 | 17496 | 22420167 |
Compute more
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Technical details
- Node id
n-45c08373a943b8b4· revision 0 · JSON- Definition source
derived:one_plus_derivative- Fingerprint
f6-8a8ae75bcd9de4e8
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: 9, 6; 2: 54, 96, 27; 3: 288, 906, 657, 108; 4: 1440, 6576, 8820, 3672, 405; 5: 6912, 41568, 83808, 65772, 18225, 1458; 6: 32256, 241152, 655488, 790992, 416826, 83592, 5103; 7: 147456, 1319424, 4531968, 7502976, 6174144, 2364390, 362313, 17496; 8: 663552, 6918144, 28781568, 61005312, 69802560, 42200352, 12369672, 1504656, 59049; 9: 2949120, 35119104, 171786240, 445436928, 659508480, 560260800, 261320256, 60833592, 6042681, 196830;
%F FormulaThe row polynomials satisfy -(6*n^3-15*n^2+9*n-(6*n^3-17*n^2+30*n-19)*x-(12*n^2-19*n+6)*x^2-6*n*x^3)*P(n,x) = -(24*n^3-36*n^2-24*n+36+(30*n^3-49*n^2-125*n+144)*x-(54*n^3-87*n^2+98*n-74)*x^2-(108*n^2-129*n+69)*x^3-(54*n-18)*x^4)*P(n-1,x) + ((12*n^2-12)*x+(24*n^2+16*n-46)*x^2-(36*n^2-24*n+16)*x^3-(72*n-30)*x^4-36*x^5)*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^3 - 36*n^2 - 24*n + 36 + (30*n^3 - 49*n^2 - 125*n + 144)*x - (54*n^3 - 87*n^2 + 98*n - 74)*x^2 - (108*n^2 - 129*n + 69)*x^3 - (54*n - 18)*x^4)*P[n - 1, x] + ((12*n^2 - 12)*x + (24*n^2 + 16*n - 46)*x^2 - (36*n^2 - 24*n + 16)*x^3 - (72*n - 30)*x^4 - 36*x^5)*D[P[n - 1, x], x])/(-6*n^3 + 15*n^2 - 9*n + (6*n^3 - 17*n^2 + 30*n - 19)*x + (12*n^2 - 19*n + 6)*x^2 + 6*n*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^3 - 36*n^2 - 24*n + 36 + (30*n^3 - 49*n^2 - 125*n + 144)*x - (54*n^3 - 87*n^2 + 98*n - 74)*x^2 - (108*n^2 - 129*n + 69)*x^3 - (54*n - 18)*x^4)*v[i - 1] + ((12*n^2 - 12)*x + (24*n^2 + 16*n - 46)*x^2 - (36*n^2 - 24*n + 16)*x^3 - (72*n - 30)*x^4 - 36*x^5)*deriv(v[i - 1], x))/(-6*n^3 + 15*n^2 - 9*n + (6*n^3 - 17*n^2 + 30*n - 19)*x + (12*n^2 - 19*n + 6)*x^2 + 6*n*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 (−∞, 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 T(n,k), 0 <= k <= n, read by rows defined by: T(n,k) = (binomial(2*n,2*k) + binomial(2*n+…?
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Geometric basis map (elementary) polytool ? step ›
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from
Triangle T(n,k), 0 <= k <= n, read by rows defined by: T(n,k) = (binomial(2*n,2*k) + binomial(2*n+1,2*k))/2.?
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Affine, reversal and Möbius substitutions (elementary) polytool ? step ›
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from
Triangle T(n,k), 0 <= k <= n, read by rows defined by: T(n,k) = (binomial(2*n,2*k) + binomial(2*n+1,2*k))/2.?
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from
basis_map_A013610 of Triangle T(n,k), 0 <= k <= n, read by rows defined by: T(n,k) = (binomial(2*n,2*k) + binomial(2*n+…?
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