A257626 → D+1
nonnegative coefficients
Proved for all n all roots real, in (−∞, 0]coefficients of one signHadamard kernelinterlacing (weak)
Recurrence
\(\left(-1 + 2\,x + n\right)\,P_{n}(x) = \left(-108\,x + 108\,x^{2} - 36\,x^{3} - 54\,n + 54\,n x - 90\,n x^{2} + 36\,n x^{3} - 18\,n x^{4} - 36\,n^{2} x + 18\,n^{2} x^{2} - 27\,n^{2} x^{3} - 9\,n^{3} x^{2}\right)\,P_{n-2}(x) + \left(-36\,x^{2} + 54\,x^{3} - 36\,x^{4} + 18\,x^{5} - 18\,n x + 27\,n x^{2} - 36\,n x^{3} + 27\,n x^{4} - 9\,n^{2} x^{2} + 9\,n^{2} x^{3}\right)\,P_{n-2}'(x) + \left(-9 + 33\,x - 12\,x^{2} + 6\,x^{3} + 15\,n - 9\,n x + 15\,n x^{2} + 6\,n^{2} x\right)\,P_{n-1}(x) + \left(-3\,x + 9\,x^{2} - 6\,x^{3} + 3\,n x - 3\,n x^{2}\right)\,P_{n-1}'(x)\)
\(P_{0}(x) = 1\)
\(P_{1}(x) = 12 + 6\,x\)
Rows ?
| n | x0 | x1 | x2 | x3 | x4 | x5 | x6 | x7 | x8 | x9 | x10 | x11 | x12 | x13 | x14 | Pn(1) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | 1 | 1 | ||||||||||||||
| 1 | 12 | 6 | 18 | |||||||||||||
| 2 | 144 | 180 | 36 | 360 | ||||||||||||
| 3 | 1620 | 4212 | 2052 | 216 | 8100 | |||||||||||
| 4 | 17172 | 83268 | 81324 | 21060 | 1296 | 204120 | ||||||||||
| 5 | 173988 | 1451196 | 2569968 | 1307340 | 205092 | 7776 | 5715360 | |||||||||
| 6 | 1705860 | 23062644 | 68526000 | 62081640 | 18997740 | 1939140 | 46656 | 176359680 | ||||||||
| 7 | 16332516 | 342580428 | 1608521004 | 2408761800 | 1298071980 | 259579404 | 18012132 | 279936 | 5952139200 | |||||||
| 8 | 153711108 | 4840889508 | 34308912420 | 80027167644 | 70617223980 | 24721401852 | 3408649452 | 165468420 | 1679616 | 218245104000 | ||||||
| 9 | 1428749604 | 65894668668 | 680504138136 | 2359796365908 | 3215561478984 | 1832459192676 | 441754701912 | 43587373644 | 1509371172 | 10077696 | 8642506118400 | |||||
| 10 | 13161077316 | 871932886740 | 12764686102920 | 63443010875040 | 127377465319440 | 111505811682888 | 43615110140280 | 7547085757440 | 547321638060 | 13705272900 | 60466176 | 367699351219200 | ||||
| 11 | 120445079652 | 11290709925036 | 229261815700020 | 1586591128663920 | 4521383387329320 | 5800725439114536 | 3474731578463208 | 974478745352880 | 124826658350580 | 6786136647180 | 124073050212 | 362797056 | 16730320480473600 | |||
| 12 | 1097066410884 | 143788345684740 | 3979440324510876 | 37466339245324020 | 147082881877946280 | 266266812373024392 | 233035163157255480 | 99935677066257288 | 20765191134405780 | 2016165145775220 | 83390513942124 | 1121011016580 | 2176782336 | 810777069438336000 | ||
| 13 | 9958492209060 | 1807668295216092 | 67225712006126592 | 845010613273603356 | 4460743369706926140 | 11051365502050353720 | 13600482548350769856 | 8508089044842056856 | 2702532332722176828 | 426814917684798060 | 31996425941781120 | 1018206610031052 | 10115220537252 | 13060694016 | 41697106428257280000 | |
| 14 | 90174979030212 | 22498187226542388 | 1111273591446490464 | 18362608611758006040 | 127799050325564970756 | 422649346338984367836 | 708954355778244475104 | 622455700150732491792 | 288271682511317541900 | 69649811034571909548 | 8532568026610172352 | 501138392383608408 | 12375301299097644 | 91193713163460 | 78364164096 | 2268322589697196032000 |
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Technical details
- Node id
n-4969942ab2f8f858· revision 0 · JSON- Definition source
derived:one_plus_derivative- Fingerprint
f6-9f7813ee7004ecb1
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: 12, 6; 2: 144, 180, 36; 3: 1620, 4212, 2052, 216; 4: 17172, 83268, 81324, 21060, 1296; 5: 173988, 1451196, 2569968, 1307340, 205092, 7776; 6: 1705860, 23062644, 68526000, 62081640, 18997740, 1939140, 46656; 7: 16332516, 342580428, 1608521004, 2408761800, 1298071980, 259579404, 18012132, 279936; 8: 153711108, 4840889508, 34308912420, 80027167644, 70617223980, 24721401852, 3408649452, 165468420, 1679616; 9: 1428749604, 65894668668, 680504138136, 2359796365908, 3215561478984, 1832459192676, 441754701912, 43587373644, 1509371172, 10077696;
%F FormulaThe row polynomials satisfy (n-1+2*x)*P(n,x) = -(54*n+(36*n^2-54*n+108)*x+(9*n^3-18*n^2+90*n-108)*x^2+(27*n^2-36*n+36)*x^3+18*n*x^4)*P(n-2,x) - (18*n*x+(9*n^2-27*n+36)*x^2-(9*n^2-36*n+54)*x^3-(27*n-36)*x^4-18*x^5)*d/dx P(n-2,x) + (15*n-9+(6*n^2-9*n+33)*x+(15*n-12)*x^2+6*x^3)*P(n-1,x) + ((3*n-3)*x-(3*n-9)*x^2-6*x^3)*d/dx P(n-1,x) for n >= 2, with P(0,x) = 1, P(1,x) = 12 + 6*x.
%t MathematicaP[0, x_] := 1;
P[1, x_] := 12 + 6*x;
P[n_, x_] := P[n, x] = Expand[Together[(-(54*n + (36*n^2 - 54*n + 108)*x + (9*n^3 - 18*n^2 + 90*n - 108)*x^2 + (27*n^2 - 36*n + 36)*x^3 + 18*n*x^4)*P[n - 2, x] - (18*n*x + (9*n^2 - 27*n + 36)*x^2 - (9*n^2 - 36*n + 54)*x^3 - (27*n - 36)*x^4 - 18*x^5)*D[P[n - 2, x], x] + (15*n - 9 + (6*n^2 - 9*n + 33)*x + (15*n - 12)*x^2 + 6*x^3)*P[n - 1, x] + ((3*n - 3)*x - (3*n - 9)*x^2 - 6*x^3)*D[P[n - 1, x], x])/(n - 1 + 2*x)]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten%o PARI/GPP(N) = {my(v = vector(N + 1)); v[1] = 1; v[2] = 12 + 6*x; for(n = 2, N, my(i = n + 1); v[i] = (-(54*n + (36*n^2 - 54*n + 108)*x + (9*n^3 - 18*n^2 + 90*n - 108)*x^2 + (27*n^2 - 36*n + 36)*x^3 + 18*n*x^4)*v[i - 2] - (18*n*x + (9*n^2 - 27*n + 36)*x^2 - (9*n^2 - 36*n + 54)*x^3 - (27*n - 36)*x^4 - 18*x^5)*deriv(v[i - 2], x) + (15*n - 9 + (6*n^2 - 9*n + 33)*x + (15*n - 12)*x^2 + 6*x^3)*v[i - 1] + ((3*n - 3)*x - (3*n - 9)*x^2 - 6*x^3)*deriv(v[i - 1], x))/(n - 1 + 2*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]
-
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
Related ?
Same fingerprint ?
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.