A116414 → basis A007318 → (θ+1)²
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(1352\,n + 130\,n x + 50\,n x^{2} - 260\,n^{3} x^{2} - 50\,n^{3} x^{3} + 2\,n^{5} x^{4}\right)\,P_{n}(x) = \left(3380 + 1846\,x + 450\,x^{2} + 22\,x^{3} - 10\,x^{4} + 3380\,n + 3029\,n x + 385\,n x^{2} - 199\,n x^{3} - 55\,n x^{4} + 1183\,n^{2} x - 715\,n^{2} x^{2} - 541\,n^{2} x^{3} - 90\,n^{2} x^{4} + n^{2} x^{5} - 650\,n^{3} x^{2} - 346\,n^{3} x^{3} - 45\,n^{3} x^{4} + 3\,n^{3} x^{5} - 26\,n^{4} x^{3} + 5\,n^{4} x^{4} + 3\,n^{4} x^{5} + 5\,n^{5} x^{4} + n^{5} x^{5}\right)\,P_{n-1}(x) + \left(2197 + 2535\,x + 806\,x^{2} - 10\,x^{3} - 51\,x^{4} - 5\,x^{5} - 1183\,n x^{2} - 1235\,n x^{3} - 341\,n x^{4} - 25\,n x^{5} - 1183\,n^{2} x^{2} - 1235\,n^{2} x^{3} - 328\,n^{2} x^{4} - 15\,n^{2} x^{5} + n^{2} x^{6} + 26\,n^{3} x^{4} + 20\,n^{3} x^{5} + 2\,n^{3} x^{6} + 13\,n^{4} x^{4} + 10\,n^{4} x^{5} + n^{4} x^{6}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | |||||||
| 1 | 5 | 4 | 9 | ||||||
| 2 | 22 | 40 | 9 | 71 | |||||
| 3 | 95 | 276 | 135 | 16 | 522 | ||||
| 4 | 409 | 1640 | 1269 | 320 | 25 | 3663 | |||
| 5 | 1760 | 9008 | 9630 | 3808 | 625 | 36 | 24867 | ||
| 6 | 7573 | 47160 | 64611 | 35200 | 9000 | 1080 | 49 | 164673 | |
| 7 | 32585 | 239068 | 400275 | 279440 | 98125 | 18252 | 1715 | 64 | 1069524 |
Compute more
?
Technical details
- Node id
n-5a3919624eaffe04· revision 0 · JSON- Definition source
derived:theta_plus_one_squared- Fingerprint
f6-47fb531231568563
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: 5, 4; 2: 22, 40, 9; 3: 95, 276, 135, 16; 4: 409, 1640, 1269, 320, 25; 5: 1760, 9008, 9630, 3808, 625, 36; 6: 7573, 47160, 64611, 35200, 9000, 1080, 49; 7: 32585, 239068, 400275, 279440, 98125, 18252, 1715, 64; 8: 140206, 1184200, 2345445, 2003200, 900250, 229320, 33271, 2560, 81; 9: 603275, 5764620, 13190850, 13347360, 7336875, 2388204, 473340, 56064, 3645, 100;
%F FormulaThe row polynomials satisfy (1352*n+130*n*x-(260*n^3-50*n)*x^2-50*n^3*x^3+2*n^5*x^4)*P(n,x) = (3380*n+3380+(1183*n^2+3029*n+1846)*x-(650*n^3+715*n^2-385*n-450)*x^2-(26*n^4+346*n^3+541*n^2+199*n-22)*x^3+(5*n^5+5*n^4-45*n^3-90*n^2-55*n-10)*x^4+(n^5+3*n^4+3*n^3+n^2)*x^5)*P(n-1,x) + (2197+2535*x-(1183*n^2+1183*n-806)*x^2-(1235*n^2+1235*n+10)*x^3+(13*n^4+26*n^3-328*n^2-341*n-51)*x^4+(10*n^4+20*n^3-15*n^2-25*n-5)*x^5+(n^4+2*n^3+n^2)*x^6)*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[((3380*n + 3380 + (1183*n^2 + 3029*n + 1846)*x - (650*n^3 + 715*n^2 - 385*n - 450)*x^2 - (26*n^4 + 346*n^3 + 541*n^2 + 199*n - 22)*x^3 + (5*n^5 + 5*n^4 - 45*n^3 - 90*n^2 - 55*n - 10)*x^4 + (n^5 + 3*n^4 + 3*n^3 + n^2)*x^5)*P[n - 1, x] + (2197 + 2535*x - (1183*n^2 + 1183*n - 806)*x^2 - (1235*n^2 + 1235*n + 10)*x^3 + (13*n^4 + 26*n^3 - 328*n^2 - 341*n - 51)*x^4 + (10*n^4 + 20*n^3 - 15*n^2 - 25*n - 5)*x^5 + (n^4 + 2*n^3 + n^2)*x^6)*D[P[n - 1, x], x])/(1352*n + 130*n*x - (260*n^3 - 50*n)*x^2 - 50*n^3*x^3 + 2*n^5*x^4)]];
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] = ((3380*n + 3380 + (1183*n^2 + 3029*n + 1846)*x - (650*n^3 + 715*n^2 - 385*n - 450)*x^2 - (26*n^4 + 346*n^3 + 541*n^2 + 199*n - 22)*x^3 + (5*n^5 + 5*n^4 - 45*n^3 - 90*n^2 - 55*n - 10)*x^4 + (n^5 + 3*n^4 + 3*n^3 + n^2)*x^5)*v[i - 1] + (2197 + 2535*x - (1183*n^2 + 1183*n - 806)*x^2 - (1235*n^2 + 1235*n + 10)*x^3 + (13*n^4 + 26*n^3 - 328*n^2 - 341*n - 51)*x^4 + (10*n^4 + 20*n^3 - 15*n^2 - 25*n - 5)*x^5 + (n^4 + 2*n^3 + n^2)*x^6)*deriv(v[i - 1], x))/(1352*n + 130*n*x - (260*n^3 - 50*n)*x^2 - 50*n^3*x^3 + 2*n^5*x^4)); 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 multiplier sequences
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Hadamard kernel (Malo)?
Rows P_n, n ≥ 0, are Hadamard kernels (preserve real-rootedness)
derived from Laguerre’s theorem on multiplier sequences
- 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 multiplier sequences [SP14; Bra15, Thm 7.1 of arXiv:1410.6601] polytool ? step ›
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from
basis_map_A007318 of Riordan array (1/((1-x)(1-3x)),x/((1-x)(1-3x))).?
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Geometric basis map (elementary) polytool ? step ›
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from
basis_map_A007318 of Riordan array (1/((1-x)(1-3x)),x/((1-x)(1-3x))).?
References
- [Bra15] Petter Brändén. Unimodality, log-concavity, real-rootedness and beyond. Handbook of enumerative combinatorics, :437–483, March 2015. doi:10.1201/b18255-10
- [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