A121314 → D+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(6 - 12\,x + 39\,x^{2} - 12\,x^{3} - 10\,n + 32\,n x - 50\,n x^{2} + 8\,n x^{3} + 4\,n^{2} - 28\,n^{2} x + 16\,n^{2} x^{2} + 8\,n^{3} x\right)\,P_{n}(x) = \left(6 + 30\,x + 41\,x^{2} + 55\,x^{3} - 28\,x^{4} - 10\,n - 34\,n x - 16\,n x^{2} - 102\,n x^{3} + 24\,n x^{4} + 4\,n^{2} - 4\,n^{2} x - 44\,n^{2} x^{2} + 48\,n^{2} x^{3} + 8\,n^{3} x + 24\,n^{3} x^{2}\right)\,P_{n-1}(x) + \left(2\,x + 10\,x^{2} + 13\,x^{3} + 16\,x^{4} - 16\,x^{5} - 2\,n x - 6\,n x^{2} - 32\,n x^{4} - 4\,n^{2} x^{2} - 16\,n^{2} x^{3}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | x9 | x10 | x11 | x12 | x13 | x14 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | ||||||||||||||
| 1 | 1 | 1 | 2 | |||||||||||||
| 2 | 1 | 3 | 1 | 5 | ||||||||||||
| 3 | 1 | 7 | 6 | 1 | 15 | |||||||||||
| 4 | 1 | 11 | 23 | 10 | 1 | 46 | ||||||||||
| 5 | 1 | 15 | 52 | 55 | 15 | 1 | 139 | |||||||||
| 6 | 1 | 19 | 93 | 168 | 110 | 21 | 1 | 413 | ||||||||
| 7 | 1 | 23 | 146 | 381 | 434 | 196 | 28 | 1 | 1210 | |||||||
| 8 | 1 | 27 | 211 | 726 | 1215 | 966 | 322 | 36 | 1 | 3505 | ||||||
| 9 | 1 | 31 | 288 | 1235 | 2761 | 3267 | 1932 | 498 | 45 | 1 | 10059 | |||||
| 10 | 1 | 35 | 377 | 1940 | 5460 | 8723 | 7755 | 3564 | 735 | 55 | 1 | 28646 | ||||
| 11 | 1 | 39 | 478 | 2873 | 9780 | 19838 | 24024 | 16731 | 6171 | 1045 | 66 | 1 | 81047 | |||
| 12 | 1 | 43 | 591 | 4066 | 16269 | 40188 | 62244 | 59488 | 33462 | 10153 | 1441 | 78 | 1 | 228025 | ||
| 13 | 1 | 47 | 716 | 5551 | 25555 | 74613 | 141576 | 174148 | 135278 | 62920 | 16016 | 1937 | 91 | 1 | 638450 | |
| 14 | 1 | 51 | 853 | 7360 | 38346 | 129409 | 291669 | 441864 | 444210 | 286858 | 112398 | 24388 | 2548 | 105 | 1 | 1780061 |
Compute more
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Technical details
- Node id
n-45d24d88ef8e58a8· revision 0 · JSON- Definition source
derived:one_plus_derivative- Fingerprint
f6-19dd6beff63092aa
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: 1, 1; 2: 1, 3, 1; 3: 1, 7, 6, 1; 4: 1, 11, 23, 10, 1; 5: 1, 15, 52, 55, 15, 1; 6: 1, 19, 93, 168, 110, 21, 1; 7: 1, 23, 146, 381, 434, 196, 28, 1; 8: 1, 27, 211, 726, 1215, 966, 322, 36, 1; 9: 1, 31, 288, 1235, 2761, 3267, 1932, 498, 45, 1;
%F FormulaThe row polynomials satisfy (4*n^2-10*n+6+(8*n^3-28*n^2+32*n-12)*x+(16*n^2-50*n+39)*x^2+(8*n-12)*x^3)*P(n,x) = (4*n^2-10*n+6+(8*n^3-4*n^2-34*n+30)*x+(24*n^3-44*n^2-16*n+41)*x^2+(48*n^2-102*n+55)*x^3+(24*n-28)*x^4)*P(n-1,x) - ((2*n-2)*x+(4*n^2+6*n-10)*x^2+(16*n^2-13)*x^3+(32*n-16)*x^4+16*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[((4*n^2 - 10*n + 6 + (8*n^3 - 4*n^2 - 34*n + 30)*x + (24*n^3 - 44*n^2 - 16*n + 41)*x^2 + (48*n^2 - 102*n + 55)*x^3 + (24*n - 28)*x^4)*P[n - 1, x] - ((2*n - 2)*x + (4*n^2 + 6*n - 10)*x^2 + (16*n^2 - 13)*x^3 + (32*n - 16)*x^4 + 16*x^5)*D[P[n - 1, x], x])/(4*n^2 - 10*n + 6 + (8*n^3 - 28*n^2 + 32*n - 12)*x + (16*n^2 - 50*n + 39)*x^2 + (8*n - 12)*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] = ((4*n^2 - 10*n + 6 + (8*n^3 - 4*n^2 - 34*n + 30)*x + (24*n^3 - 44*n^2 - 16*n + 41)*x^2 + (48*n^2 - 102*n + 55)*x^3 + (24*n - 28)*x^4)*v[i - 1] - ((2*n - 2)*x + (4*n^2 + 6*n - 10)*x^2 + (16*n^2 - 13)*x^3 + (32*n - 16)*x^4 + 16*x^5)*deriv(v[i - 1], x))/(4*n^2 - 10*n + 6 + (8*n^3 - 28*n^2 + 32*n - 12)*x + (16*n^2 - 50*n + 39)*x^2 + (8*n - 12)*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]
-
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
-
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
References
- [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.